Line #173 VideoGame/MetalSlugDefense


1	[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/23194414509_4175a39e12_b.jpg]]
2
3	''Metal Slug Defense'' is a mobile game released rather suddenly by SNK in 2014. Despite the title, it is not quite a TowerDefense, but rather a strategy game set in the ''VideoGame/MetalSlug'' universe. Players spend a constantly filling meter on various characters and enemies from the series, which then march forward in hopes of overwhelming and destroying the opposite base. The many different human, machine and monster units have a basic attack, as well as unique charged moves which sometimes require good timing to be used correctly.
4
5	The game can be played online with friends or random people. As it is a free-to-play game, there are elements such as layers of level grinding, missions costing credits that recharge over time and most of the unlockable characters only being available through a secondary currency more accessible for those willing to spend money on it.
6
7	However, all updates to ''Metal Slug Defense'' have stopped since late 2015, though this doesn't mean the game services have been discontinued as its still playable to this day, either offline or online. However still, that's planned to be changed as [[https://www.snk-corp.co.jp/us/press/2022/101202/ the mobile version will end service on Monday, April 17, 2023]]. Fortunately, the game will still be playable on PC via Steam.
8
9	A sequel by the name of ''VideoGame/MetalSlugAttack'' had since been released in February 2016, which vastly improves over ''MSD'' in certain aspects and saw constant updates. However, that game's service has ended on Thursday, January 12, 2023.
10	----
11	!Tropes:
12	* ActionBomb: The Zombie Rebel Soldier, Mutated Soldier, and the Hopper Mecha units self-destruct upon reaching a target. Meanwhile, the Special Force (Rider) needs to rev up his bike before he can crash into an enemy and deal some damage. The player can also release an explosive SV 001 once the "Metal Slug Attack" meter is filled.
13	* AdaptationalWimp: The four protagonists of the original team of pretty weak in this game.
14	* ActuallyFourMooks: The Hover Unit is deployed in groups of three to justify their high AP cost.
15	* AdvancingBossOfDoom:
16	** Every enemy is moving towards the player's base, after all. Even ones such as Jupiter King, who originally moved away.
17	** The Huge Hermit - who is the only enemy on its mission - even instakills anything it hits, no matter how much health the target has…''except'' the [[https://www.youtube.com/watch?v=EWffjEYmd0Q Stone Turtle]], which can even block it.
18	** The Stone Turtle, whose regular attack consists of stomping the unit in front of it for huge damage, but moves very slowly towards the other side. It also has a ''huge'' amount of health.
19	** Rugal Bernstein as a boss (actually the [[SNKBoss SNK Boss]]) in Black Noah Attack event starts off with a hyper armor which its impossible to knock him back and he can reach your base in just 5 seconds if don't act quick. Good luck and make sure you have better units because this guy has chunks of HP and his attacks are already deadly as it is.
20	** In the Missions tab, you get to fight Big Shiee (the boss from Metal Slug 2[=/=]X, Mission 3).
21	* AirborneMook:
22	** Several of them. Of note is that some can only attack once (or a few times) before leaving the battlefield, but can fly over most enemy forces without being attacked. However, later updates include air units that don't leave the map after attacking, making them quite a threat.
23	** The Smasher is normally a grounded unit, but it begins to fly before it attacks with a GroundPound.
24	** Hunter Walkers are normally grounded units, but its special ability allows it to CeilingCling and start dropping eyeball bombs in a manner similar to General Morden's Hi-Do special, though the bomb can be blocked from hitting the base if it hits a large unit.
25	* AllegedlyFreeGame: The existence of premium currency (Medals) and an energy system (Sortie Points) mean that those who are willing to cough up enough money will always have an advantage over free players.
26	* AlwaysAccurateAttack:
27	** Tetsuyuki sometimes fires a laser that hits the entire field, player base included.
28	** Morden's special is to summon the Hi-Do to drop bombs everywhere. The Hi-Do cannot be damaged at all, and it will drop at least one bomb on the enemy base, making it guaranteed to do damage.
29	* AnnouncerChatter: The announcer does his thing when the main characters use their special attack, such as Marco using the HEAVY MACHINE GUN or Fio using the ROCKET LAUNCHER, for example.
30	* AntiAir: Certain units have attacks that either shoot projectiles in an arc or at a high angle, allowing them to damage aerial units. The most notable example is the Ptolemaic "Gunnner Unit" (sic), whose special attack sprays bullets in a wide angle.
31	* AntiPoopSocking: Missions cost a certain amount of Sortie points which recharge over time. It actually isn't too troublesome after you expand the Sortie point limit to over 400... Unless you're playing the latter levels over and over to get prisoners.
32	* ArtShift: Ralf, Clark, and Leona use their sprites from the ''Metal Slug'' games (which are re-edits of Marco, Tarma, and Eri respectively), while the rest of the King of Fighters cast have a redrawn rendition of their fighting sprites.
33	* AscendedExtra:
34	** Sandbags, usually used by grenade-wielders of the Rebel Army for protection, are an essential tool for survival in this game.
35	** The Rebel Army's own soldiers (who usually don't last very long) can prove to be surprisingly effective units if properly used or upgraded.
36	* AsteroidsMonster: The Man Eater plant's special attack is to turn into two seeds that spawn little man eaters.
37	* AttackAttackAttack: All units will advance forward and exchange fire with enemies until they are killed.
38	* AwesomeButImpractical:
39	** Zombie Marco's powerful and far-reaching blood vomit jet takes a long time to charge up, especially after being used once. Meanwhile he fights with a gun much weaker than normal Marco's and gets face-to-face with enemies despite being a gun user. And upon being hit enough to be knocked down, he takes far too long to stand up.
40	** Morden may have a great special attack, but his standard attack is not as effective as his 950 (1500 in Attack) AP cost would lead you to believe and he tends to get knocked back often, leaving the rest of your units exposed as he tries to make his way back to the front.
41	** The Commander. His ability to summon Hover Units (and reset that cooldown) seems very awesome, until you find out that said Hover Units give the opponent a pretty good amount of AP if destroyed, making the Commander more of a liability than an asset.
42	* BigBad: Morden actually fights on an alien tank without being betrayed this time. The Mars People receive more focus in the last set of bonus levels. While not much of the Amadeus Syndicate is seen in the game, an expansion later added a bunch of units and some levels from the Ptolemaic Army, and later some units from the Invaders too.
43	* BigCreepyCrawlies: The Maggot, Snail, Huge Locust and Giant Caterpillar units.
44	* BigfootSasquatchAndYeti: The Sasquatch is one of the better close-range characters due to its speed and high stats.
45	* BlindIdiotTranslation: Let's just say that English is ''not'' the first language of whomever is doing the translation for the unit descriptions. It's thankfully not a TranslationTrainWreck, but it just barely gets the point across at times.
46	* BonusDungeon:
47	** At certain hours, a harder set of missions becomes available for 60 minutes. A 100% clear set will become permanently available, setting the next one to appear later. There are twelve total: 4 for Worlds 1, 2, and 3.
48	** The Extra World has 9 standard high-sortie-point locations, with the special mission cycling through each day of the week. Note that most of these missions qualify as HarderThanHard.
49	** Mission Mode itself is a gallery of levels with 1 of 2 set conditions (destroy enemy base in X seconds or survive enemy waves for X seconds) designed to showcase the Medal-unlockable units, but it gets surprisingly difficult quite fast (in combination due to [[HarderThanHard the given difficulty level]] and [[GuideDangIt figuring out the trick for each unit]]).
50	* BoringButPractical:
51	** The Rebel Rifleman has a bit less HP than the basic soldier, but is still cheap at 60 AP and shoots from afar while protected by tougher units. The Bikers cost 90 AP but have 1000 HP at level 20 and move faster, while otherwise acting just like the riflemen and complementing them well.
52	** The Iron Iso is a stationary tank-turned-artillery-turret that fires long-range piercing shells. That's all it does, but you'd be surprised how much it can accomplish if you keep building them in the same area.
53	** The sandbag during early-game. It doesn't attack and serves to protect, but it can stop a Metal Slug Attack and take a good amount of damage during the early game, enough for you to improve your AP regeneration or amass enough AP for a good amount of units.
54	* BossArenaUrgency: The Huge Hermit crushes the bridge on its way to the player.
55	* BossBattle: Some bosses from the first trilogy such as Shoe & Karn, Iron Nokana and Monoeye show up in certain levels, usually spawning when your units get close to the enemy base.
56	** It is also possible to purchase some of these units in the shop, and thus deploy them in missions.
57	* BottomlessMagazines: In a moment of weakness, units only reload their weapons after using a special attack.
58	* BribingYourWayToVictory: Silver Medals can be used to buy items that grant advantages in the missions, such as [[TooAwesomeToUse beginning with full AP regeneration]], getting more money after clearing a mission or even unlocking all missions at once. Most units can only be bought with Silver Medals, too.
59	* TheBusCameBack: Enemies and characters that showed up in one game return for this game.
60	* TheCameo: Every heroic character from the series is at least mentioned in the game, even those from the ''Mission'' and ''Advance'' spin-offs, the Ikari Warriors (including Whip and Heidern), the rest of ''VideoGame/TheKingOfFighters '94/'95'' cast, and even [[NoExportForYou the other mobile spin-off titles.]] The villain side doesn't get such attention, though recent updates have been trying to rectify that with new units and extra missions.
61	* {{Cap}}:
62	** The level cap for units and the player base's attributes is normally 10, but it expands to 20 once the second world is unlocked, and then the base upgrades cap at 30 once the third world is unlocked. The unit level cap, on the other hand, can only be upgraded to 25 by using Silver Medals. Later updates increased the level cap for units further and the posibility to use MSP to increase said cap up to 35. During gameplay, AP recharge speed can be improved 10 times and there is also a limit to how many units can be sent at once.
63	* CastOfExpies: Many of the OriginalGeneration characters are either an {{Expy}} of a character from another work or have a ShoutOut to another work in their design. Details are in the character sheets.
64	* ChargedAttack: Most units can use a special move by spending a meter that fills over time. Oddly, few CPU characters use their special move until the player gets to World 3.
65	* ChristmasEpisode: The December events in both games. Appropriately, these also have Christmas themed versions of Eri and Fio, whose weapons are stronger due to their anger from being sent out during their holidays.
66	* TheComputerIsACheatingBastard:
67	** For some reason, the CPU doesn't use special moves until World 3 but it does work [[MyRulesAreNotYourRules by its own rules]] in regards to unit creation. It spawns powerful high-cost units from out of nowhere once you get close or hit its base.
68	** The difficulty of World 3 mostly comes from the enemy units actually using their special attacks whenever possible, on top of the CPU instantly spawning units at certain conditions.
69	* CounterAttack: The scientist zombies don't normally attack, but when they are knocked back (which is almost every time they get hit), they gain a brief moment of invincibility before they launch a powerful short-ranged projectile.
70	* DeathFromAbove: The Parachute Truck. It fires a bunch of bombs into the air that rain down and pierce enemies until they hit the ground.
71	* DefeatMeansPlayable: Clearing a set of levels usually means unlocking the enemies featured in them... [[DoubleUnlock to be bought at the shop.]] The ones unlocked by collecting certain sets of prisoners or getting login bonuses are granted for immediate use, though. Tetsuyuki, Dragon Nosuke and Huge Hermit are unplayable due to being overpowered living bases. The trains from the subway levels can't be unlocked, either.
72	* DualBoss: Some missions like to spawn large enemies such as Shoe and Karn or all three Ohumein-Conga at once at some point.
73	* EliteMook:
74	** The Ptolemaic army units are this compared to their Rebel army counterparts, with their higher HP and the AP cost to go with it, though they do have different methods of attacking.
75	** The Future rebel is this compared to every soldier. Even their most basic infantry have 1000 HP at level one.
76	* {{Engrish}}: It's practically a SNK trademark.
77	* EverythingsDeaderWithZombies:
78	** The zombie enemies from ''Metal Slug 3'' are present. This includes Zombie Marco, who can vomit a danguerous jet of blood.
79	** The artwork for World 3 are the same artwork from the previous worlds, edited to make the characters look like zombies. This includes the Mars People for some reason.
80	* EverythingFades: Dead units may [[NoBodyLeftBehind fade, melt or explode.]]
81	* EvilLaugh: Allen ''frequently'' laughs while attacking. Morden only laughs in his victory pose or if he uses his special.
82	* [[EvolvingCredits Evolving Title Screen]]: Clearing World 1 makes Satiko Suzuki (the grieving woman) appear on the title screen. Clearing World 2 makes a UFO fly by in the background. Clearing World 3 adds destroyed tanks to the lower-right side.
83	* ExcusePlot: Morden and the martians are up to no good, so send waves of units at their bases.
84	* ExtendedGameplay: Clearing the game once unlocks a harder loop. It is more of the same in the old arenas with leveled-up enemies, but some missions can surprise the player with an out-of-place boss such as Allen. Later updates added more levels and units, as well as an mode that gives you pre-made unit decks to overcome certain situations.
85	* FailedASpotCheck: All units refuse to acknowledge the existence of aerial units, even when they are ''also aerial units''. Slow-moving air units like the Hover Vehicle depend on this AI quirk to survive.
86	* FlavorText: Each unit has a description about who they are and what they do.
87	* FinalBoss: [[spoiler:The final set of boss enemies at Final-5 in World 3 are Iron Nokana+Cyborg Allen O'Neil and then Morden+Jupiter King, supported by hordes of zombie alien clones of Fio.]]
88	* GatlingGood: Units such as Marco, some Slugs and Allen wield this weapon either normally or as their special attack.
89	* GlassCannon:
90	** The HP of the player's base isn't such an important stat to upgrade first because if a decent group of units reaches a base at all, it will most likely be done for because defending units won't have time to charge their special moves to do useful damage and can't even cover their base's hitbox.
91	** Tarma's shotgun is powerful, but he needs to get close to enemies for it to hit and if he does use it, his 720 max HP won't keep him alive for a second shot.
92	** The Commander is rather fragile for a 210 AP unit, but that's because his main attack is summoning a squad of Hover Units. His special is only a single pistol shot... which resets the cooldown of his main attack, allowing him to deploy more Hover Units faster.
93	** Patrol Robots. They don't have much health for a 160 cost unit, but their laser attack has very long range, deals continuous damage that can really add up, and also pushes back enemies very well. They're pretty slow too, however, so you'll need to defend them with more durable units.
94	** Utan. For an early-game ZergRush unit, this little monkey dies very quickly, but he has very long range (enough to avoid a Scientist Zombie's counterattack), deals good damage, and his special charges quickly and deals good burst damage.
95	* GoingThroughTheMotions: Characters don't have unique sprites for the cutscenes, only using their animations when idle or out in the field.
96	* TheGoomba: The basic blue soldier you start with. Cheap and with 400 HP at level 20. He attacks at close range with a knife and can throw grenades. The green normal rebel soldier is an unlockable and he has even less health (360 at level 20) for an even lower price.
97	* GuestFighter:
98	** The collaboration event brings the titular cats from ''VideoGame/TheBattleCats'' into the game. Explained as an accident where Morden attempts to summon the Kraken from Metal Slug 7 via his time travel portal and brings in the cats instead. Needless to say, the fans were more than displeased.
99	** The entire of ''VideoGame/TheKingOfFighters '94'' plus Whip were added to a new sixth faction.
100	* HarderThanHard: There are three difficulty levels beyond Hard: Very Hard, Expert, and Hell.
101	* HitboxDissonance:
102	** The hitbox for the bases is a bit taller than the base itself and some explosions hit farther than they should. The man that sets up barriers will flee whenever a projectile happens to fly above him, as if he was hit.
103	** The Claw Unit's special attack has a taller hitbox than what its attack animation would suggest, allowing it to hit high-flying units like the Flying Tara.
104	* HumongousMecha: [[http://metalslug.wikia.com/wiki/Jupiter_King Jupiter King]] from ''Metal Slug 3'' first appears in area 10, stage 4. The Mars Mecha is also present in the last set of bonus levels. The Gigant Units may also count, its interesting that this units are huge when you check it on your deck.
105	* IdleAnimation: The status screen for the units are where you get to see them standing still. Amusingly, rather than going through a standing animation and then a special one before looping over like everyone else, Marco is completely asleep.
106	* ImmuneToFlinching: A select few have this valuable trait, and most of them are great meatshields. Oddly enough, the Rebel Biker does not flinch despite having low HP commonly found among infantry units, and in an interesting twist, the shielded soldiers have such low flinch resistance that they get knocked back on every hit, but their knockback duration is so low that they might as well be immune to knockback anyway.
107	* InfinityPlusOneSword:
108	** The Mars People are unlocked on the last level set. They spam laser bubbles at a safe distance (and can fire from above by warping), cost only 80 AP and are produced very quickly. They do need a meat shield to compensate for the slowness of their bubbles, however.
109	** By logging on the game every day, you'll eventually get the Elephant Slug, which has plenty of HP and a fireball attack with great reach.
110	** Some of the units you unlock from the extra stages are more powerful than most of the other units from the main stages. In particular, extra set 1 gets you the Big Snail and the Giant Caterpillar, two of the best defensive units in the game, while beating extra set 2 unlocks the Samurai Tank, a cheap, long-range unit with a disproportionately high amount of HP.
111	** Currently, the best unit is still arguably the Jupiter King, a high-cost, long-range support unit that deals a huge chunk of damage to all enemies in a wide area in one burst. However, the scientist zombies are quickly becoming popular as they are capable of stopping early-game rushes cold and are just generally annoying to get rid of.
112	* InsurmountableWaistHeightFence: Sandbags block enemy advances until they're destroyed. In normal ''Metal Slug'' games, people would just jump over them instead.
113	* KamehameHadouken: Hyakutaro can fire energy balls from his hands.
114	* {{Knockback}}: Most units suffer from this upon being hit by powerful attacks but surviving. This is important as knockback cancels out attacks that have already been started and gives invincibility frames for the duration of the knockback.
115	* KnowWhenToFoldEm: [[http://metalslug.wikia.com/wiki/Abul_Abbas Abul Abbas]] waves a white flag and disappears when out of HP.
116	* LightningBruiser:
117	** The Natives, introduced in version 1.4.0, are cheap, yet beefy infantry units that have a fast speed and a very fast production speed. Their standard attack is above average for an infantry unit while their special attack has a ridiculous range and deals even more damage. All of this combines into a very effective shock trooper.
118	** The Green Hazmat Soldier runs as fast as Natives and has more health than most tanks, with their attacks consisting of a powerful grenade that can destroy air units and a ludicrously powerful bomb that deals huge damage to enemy units and then spawns a similarly tough (but very slow) Mummy. The current meta in Multiplayer consists of rolling out a single one of these guys to stall for time so you can build more powerful units early.
119	** Claw units are deceptively slow, but at long range they charge into the fray to maul any enemy in its way. They also have a decent production speed and a good amount of HP.
120	*** Iori Yagami, who was released as part of SNK's 20th KOF anniversary, will rush at enemies at long range before performing a 3-hit combo on them. Also applies to Vice and Mature, who both rush at enemies when attacking at long range.
121	* LimitBreak:
122	** Nearly every unit has a meter that slowly depletes to zero. Once it reaches zero, they can use their Special Attack.
123	** A [[ActionBomb self-destructing SV 001]] can be sent when its meter fills. It insta-kills a good number of small enemies before exploding upon colliding with a larger enemy or the opposing base. This is important when fighting Jupiter King, which [[InstantDeathRadius makes such a mess]] out of anything you send at it that, at least early on, you're forced to just buy time and try to get rid of large enemies until the bombastic SV 001 is available for damaging and pushing King away.
124	* LuckilyMyShieldWillProtectMe:
125	** Shielded Soldiers, who have higher HP than their fellow rebels. Their special move is to make a pushing motion, which blocks ''all'' damage. Snails, too, can hide in their shells. Some missions require you to use their defense at the right times to win.
126	** Iron Claws and Melty Honeys are ''tanks'' with abative shields on the front. With SpikesOfDoom to boot.
127	* MacrossMissileMassacre:
128	** Several units are able to fire many rocket/missile projectiles. Have a number of them on the screen and you get this trope.
129	* MadeOfIron:
130	** For obvious reasons, Allen O'Neil, a barechested soldier, has HP comparable to that of a heavy tank.
131	** Instead of dying like other pilots, when the Protogunner is destroyed, Ralf dismounts it and continues the fight on foot. He's just that tough.
132	** Most of the human units, compared to their source games. They're no longer {{One Hit Point Wonder}}s and some can take a fair bit of damage before keeling over.
133	* MadeOfPlasticine: Most mook units in general, but the Hazmat Soldier just unceremoniously falls to pieces instead of keeling over.
134	* ManOnFire: Some units have a burned animation for when they're killed by one of the few fire attacks available.
135	* {{Mecha}}: The Slugnoid, the LV Armor and the Slug Gunner.
136	* MegatonPunch:
137	** Ralf has the notorious Galactica Phantom punch as his special attack.
138	** Gunnner (sic) Units have a powerful punch as their standard attack. The Claw Units use a one-two claw punch at close range.
139	* MightyGlacier:
140	** Units that are slow to produce and slow to move, but pack a hefty punch given their AP cost. This includes...
141	** The two variants of Iron Nokana: very slow production speed, but fires bursts of 3 piercing shells, and depending on which version of Iron Nokana you use, can either use a flamethrower to quickly demolish units that come too close or launch a large salvo of long-range missiles.
142	** With the Ring Laser Mecha's AP cost reduced to 100, they've become semi-cheap walls that can wipe away most infantry and deal serious damage to other swarming units.
143	** The Stone Turtle has an attack that is highly damaging, but its walking speed is very slow.
144	* MookMaker: Mummy Generators, Crab Nests and 3-Ton Utility Trucks are obstacles that generate units. Also, Abul Abbas's special ability is to summon a Utility Truck.
145	* MundaneUtility: Aside from being able to easily murder lesser infantry, the Metal Slug Attack can also be used to destroy enemy projectiles.
146	* {{Nerf}}:
147	** The Big Snail used to be a great early-game unit when it was first introduced, having high HP and a devastating short-ranged standard attack that could destroy many other early-game units before they could attack or deliver their full potential. Now its AP cost has been increased and its production speed lowered to discourage snail rushes.
148	** The Patrol Robot used to have even longer range, allowing it to harass and knock back units from afar behind the safety of frontal units. Its range has been nerfed by quite a good bit, however, its AP cost has been lowered.
149	** When the Parachute Truck was first released, it dropped a hail of projectiles at a good range that did penetrating damage as long as they touched an opponent, decimating even the biggest units in ''seconds''. It got so bad that the following update nerfed them greatly, giving them less range, giving them a longer time to build, and making their attacks no longer penetrate.
150	* NoFairCheating:
151	** Trying to cheat by using any explicit tools that allows to cheat the game such as increasing the number of medals and sorties, the development team will make your account get suspended and cannot be recovered again once if you get caught doing this behavior which can be found in the rules.
152	* NonLethalBottomlessPits: You can see this trope by having Ralf use the Galactica Phantom to fall off Giant Hermit's bridge while the Hermit is knocked some steps away.
153	* NostalgiaLevel: All arenas are taken from the series' levels. There often is some continuity between them - you can see a piece of the next level just around the corner.
154	* OhCrap: If a Miner gets hit before setting a barrier or stationary unit, he freaks out and flees. Rumi is also shown panicking in her icon if a mission is lost. If a defeated unit has a P.O.W. helping, then he goes off running while leaving the rest to die.
155	* OneHitPolykill: Some units, like the Ring Laser Mecha, have attacks that can hit any number of enemy units within its range. This is good for dealing damage to important targets that are protected by heavier units, or for clearing away hordes of cannon-fodder units.
156	* OriginalGeneration: Eris makes her first appearance in ''Defense'' in the Relief Supplies Menu and the [=POW=] List. She hosts the Build Up section in ''Attack'' and gives her very own sprites.
157	* PaletteSwap: Issenmantaro serves as this for Hyakutaro, but more focused on close-quarters combat. The Elite Arabian Soldier serves as this for Abul Abbas; in ''Defense'', the Elite Arabian Soldier has his special attack changed to a charging strike. The Jupiter King MKII serves this as well for the original with its laser attack being replaced to [[MacrossMissileMassacre missile]].
158	* PopGoesTheHuman: The fat versions of the main characters and Chang's defeat animation.
159	* PromotedToPlayable: Almost everything, from the regular mook to those badass bosses although some units like the Big Shiee will stay as a boss and will not be playable until several updates later. In ''Attack'' some units from ''Defense'' like the Subway unit that were never playable becomes playable and becomes present in online game play.
160	* RandomlyDrops:
161	** Upgrades are unlocked upon rescuing sets of prisoners, but the prisoners aren't seen in the levels and seem to be saved at random upon finishing a mission, [[FakeLongevity to force replays.]] It's [[LastLousyPoint especially annoying]] in regards to [[ThatOneLevel the harder]], [[AntiPoopSocking expensive]] missions and the bonus ones that are only available for a short time on each day. Of course, you can use [[BribingYourWayToVictory silver medals]] to buy items that guarantee that one prisoner will appear.
162	** Completing the extra stages sometimes awards you with a powerup. How it works is not yet determined.
163	** With the 1.5.0 update, random collectibles, such as extra AP, MSP, and Sortie points, can be found within stages. You collect them by having units attack the spot where they're hiding. This is also how you can rescue [=POWs=] even if you don't use the Radar item.
164	* RapidFireFisticuffs: Ralf uses his Vulcan Punches instead of the Flame Shot if he's facing an enemy at point-blank range.
165	* SecondQuest:
166	** Beating all the stages unlocks the World 2 loop, in which enemies are stronger and have more health. To ease this, the level cap for both units and home is lifted from 10 to 20.
167	** As of version 1.8.0, beating all the World 2 stages unlocks [[HarderThanHard World 3.]] However, it also increases the base level cap to 30.
168	* SeeYouInHell: Said by Allen and his son upon dying yet again.
169	* SequentialBoss:
170	** Crablops. When its initial health reaches zero, its bottom will be destroyed, but its top will fly off and turn into another high-health unit, similar to being the second and third boss of ''Metal Slug 7''.
171	** Emain Macha ("Twins") essentially works like this. When it's deployed, it only sends out the first, green-coloured one. When that is destroyed, the second, much faster-moving one comes charging from behind the base and fights similarly to the first otherwise.
172	* ShowsDamage: Tetsuyuki and the Metal Claw are examples of units that get visible damage as they lose HP.
173	* SkillGateCharacters: Leona. She costs 80 AP, can destroy early units and bases with ease with her powerful melee attacks and special, and is very hard to handle with a beginner's deck. She falls against more experienced decks due to being melee-only- once Claw Robot and Utan are out, she becomes easy to take care of. [[TookALevelInBadass Until the sequel, that is]].
174	* SoLastSeason:
175	** Happens often especially when new and very powerful units come out, being able to counter or eclipse other units' performance.
176	** When Rebel Gigant came out, Patrol Robot was made pretty much useless thanks to the Gigant's special ability being able to penetrate through to hit and destroy them. Both Slug Gigant and Rebel Gigant could easily kill off air units, severely limiting the usefulness of them.
177	** Before a good number of the later boss units were released, Jupiter King was an extremely good, durable and powerful unit. Now it's been OvershadowedByAwesome by a huge number of later bosses, not helped by the fact that it doesn't have a regular attack.
178	* StationaryBoss: Tetsuyuki, a fallen warship used as a base by the rebels in ''Metal Slug 1''. Every once in a while it shoots an unavoidable laser.
179	* StoneWall:
180	** Units that have tons of HP but have little attack power on their own, such as the Giant Caterpillar and the Mars Mecha. They are essential for protecting your more powerful units from harm so that they can deal more damage before they get destroyed. The Ohumein-Congas and the Giant Caterpillar are notable for having a special attack that brings them directly to the front of your attack force, shielding the rest of your units from attacks. Donald Morden can also be used to stone wall (albeit a very expensive one), simply for having the highest HP among all units.
181	** The Augensterm, introduced in version 1.7.0, is the very definition of stone wall, having the tallest hitbox in the game and the second highest HP count while being cheaper than Iron Nokana. It has the tremendously useful knockback immunity seen in previously mentioned stone wall units, and can move while laying down machine gun fire if it is not close to the enemy.
182	** The Morden Robot, introduced in version 1.8.0, can be used as a cheap and spammable stone wall, having the HP of a midrange tank unit and possessing knockback immunity. When it is damaged, it launches its own head like a grenade and continues to limp towards the enemy to delay their advance.
183	* TakeCover: It's good practice to hide long-range units behind big, beefy units. Snipers actually use this as their special ability: they hide under a wooden box, turning themselves into stationary turrets who can take potshots from behind the rest of the army.
184	* TankGoodness: Many tanks from the series are available here, from the cute SV 001 to titanic machines such as the Iron Nokana and the Metal Rear.
185	* TeamSpirit: If a deck consists of a single faction, they all gain a 10% HP bonus.
186	* TeleportSpam: The Mars People Cadre do this while firing a barrage of alien spores as their special attack.
187	* TemporaryOnlineContent: Event units, who are available to purchase within a certain version.
188	* ThisIsADrill: The Drill Slug uses its drill as a middle-range charged attack.
189	* TimedMission:
190	** The fight against Tetsuyuki has this sense of urgency, due to the boss being able to use a laser that hits the entire field.
191	** Multiplayer battles have a 99 seconds time limit and some missions require the player to survive until the countdown ends.
192	** Mission Mode consists of nothing but these kinds of missions, as detailed under BonusDungeon.
193	* ThrowAwayGuns: The four main heroes typically throw away their special weapon upon use.
194	* ThrowingYourSwordAlwaysWorks: The Arabian Soldier unit throws his sword as a special attack. His [[FlavorText in-game description]] [[LampshadeHanging casts doubt on the usefulness of such a move.]] He does replace his sword after throwing it, though.
195	* TurnsRed:
196	** Subverted by the Iron Nokana. It is supposed to lift itself and reveal a flamethrower on its bottom when low on HP, but as here the flamethrower is its special move instead, its death animation shows it lifting only to immediately explode.
197	** Allen O'Neil surprisingly never changes color at all despite doing so in the main series. However, his very red form has been turned into a separate unit, called Allen Wrath.
198	** Allen Jr. will switch from his Gatling gun to his knife once he revives.
199	* VictoryPose: Done by any unit that had an animation for this in the main games.
200	* WalkingTank: The Slug Gunner. The Samurai Tank, amusingly, has two people holding it to move around.
201	* AWinnerIsYou: [[spoiler:''Defense'' reuses the ending scene form ''Metal Slug 3'', while talking about how the heroes will continue to battle any evildoers. The same ending plays on all three loops.]]
202	* WorthyOpponent: An interesting case where your online opponent is such- you can click a "Good Job!" button telling them that they did well against you regardless of victory/loss.
203	* YearX: The game takes place in 20XX.
204	* YouRequireMoreVespeneGas: Unit creation costs AP, which increases with time and as enemies are killed. When you have enough AP you can also spend it to make it recharge faster. One of the usable items [[BribingYourWayToVictory begins levels with a maxed AP regeneration.]]
205	* ZergRush:
206	** The descriptions for the basic Soldier and the Rebel Infantry advise this strategy, as they cost only 30 AP and have little delay between uses. A shower of their grenades sounds good in theory, but it doesn't work so well in practice because they're fragile close-range fighters. The Rebel Rifleman is a more useful unit for this strategy, as explained above.
207	** Zerg rushes can also be used with any unit that has either "Fast" or "Very Fast" production speed. With the recent updates, there are now a lot of units that qualify for zerg rushes, leading to the rise of "Rush" decks.

Context VideoGame / MetalSlugDefense