History DemonicSpiders / Metroid

*** The Chozo Ghosts are a nightmare to fight the first time you see them. They like to cloak, move around at high speeds, shoot you while you're distracted, and [[ArsonMurderAndJaywalking make loud]] [[HellIsThatNoise shrieking noises]]. Especially since they appear in multiple rooms, can only be harmed by the Power Beam (probably the weakest weapon in the game), and usually come in threes. Fortunately, the X-Ray Visor lets you see them at all times, and Super Missiles count as Power Beam damage, allowing you to take them out quickly. Navigating the Chozo Ruins (until you're ready to get the Ice Beam) is not recommended during their "appearance" phases, as you only fight them after you first encounter them in the Elder Hall. Even after you have the necessary equipment to fight back, do ''not'' go to the Arboretum again. '''Ever'''. No amount of upgrades can make fighting three of those things in a tall circular tower with a spire in the middle less of a hellish endeavor.

*** Warp Hounds. They're [[MadeOfIron ridiculously durable]], shrugging off multiple missiles and charged beam shots, and Ice Missiles don't do much. And as their name suggests, they teleport. [[TeleportSpam A lot.]] Most of the time, all you can do is shoot a charged shot or missile at them as they teleport again and again and ''again''. Facing multiple Warp Hounds at the same time is ''infuriating'' if you don't use lots and lots of [[CastFromHitPoints Hypermode]]. Just to make things worse, they love appearing in groups of three or more at a time, accompanied by the nearly as annoying (though less teleport-happy) Reptilians. Thankfully they don't do much damage, but that makes them slightly less annoying.

*** [[EliteMooks Pirate Commandos]]. They have very strong armor and attacks, and also love to go Hypermode at the slightest provocation. And after a short time in the Pirate Homeworld, they will show up '''everywhere'''. Fortunately you can [[OneHitKill shoot their weakpoints with the X-ray Visor and Nova Beam]]... but then they start coming in pairs. One of the two '''will''' use Hypermode as soon as they appear, which jams the X-ray Visor and forces you to go Hypermode and kill that one (if not both; on the otherhand, it is possible to OneHitKill a Hypermoded Pirate Commando with the Nova Beam and X-Ray Visor, but you'll still be firing blind). They make destroying the Command Center's shields much harder than it needs to be.

* The eponymous [[PersonalSpaceInvader Metroids]] themselves. In the sidescrollers they are completely invulnerable to all weapons except the Ice Beam (if you don't have it, you're screwed). While this is rarely an issue in SuperMetroid, as you can switch and combine beams, shooting through walls and freezing them at the same time while shooting diagonally, it's very possible to be without the Ice Beam in Tourian in the first game if you played without a guide, because you thought shooting through walls and dealing double damage was useful, and you didn't need the ice beam to platform any more because you had hi jump boots. After being frozen, it takes five missiles to kill them (in the first two games), it's not convenient to press the SELECT button to switch to missiles and back to the Ice Beam, and they thaw much faster than other enemies will. If one manages to grab you, the only way to get rid of it is to go into Morph Ball and drop a bunch of bombs to hopefully dislodge it (with the exception of Zero Mission, where you only need one bomb to do so)... but recovering in time to freeze them is insanely hard when they attack in groups. If you aren't very careful and quick, one will just latch right back on again. And they are very fast moving and strategically placed, and will home in at odd angles, in games where you can't shoot diagonally, letting them slip by your beam and grab you. You can advance slowly and carefully to make it easier, but that may deny you your good ending, which requires that you beat the game quickly. They are beatable, but are much more challenging than any other non boss enemy. The ''Prime'' versions lack the invulnerability, but instead obscure your vision when they latch on and still need bombs to dislodge (but thankfully only one). In ''Corruption'', you have no Ice Beam, but Ice Missiles, which the Metroids dodge by turning intangible--you must bait them into attacking to make the shot connect!

* The eponymous [[PersonalSpaceInvader Metroids]] themselves. In the sidescrollers they are completely invulnerable to all weapons except the Ice Beam (if you don't have it, you're screwed). After being frozen, it takes five missiles to kill them, and they thaw much faster than other enemies will. If one manages to grab you, the only way to get rid of it is to go into Morph Ball and drop a bunch of bombs to dislodge it (with the exception of Zero Mission, where you only need one bomb to do so)... but recovering in time to freeze them is insanely hard when they attack in groups. The ''Prime'' versions lack the invulnerability, but instead obscure your vision when they latch on and still need bombs to dislodge (but thankfully only one). In ''Corruption'', you have no Ice Beam but Ice Missiles, which the Metroids dodge by turning intangible--you must bait them into attacking to make the shot connect!

*** A pack of Ice Troopers can also be a pain as the Ice Beam is also slow to fire. Hit 'em with a charged shot, though, and [[LiterallyShatteredLives a single missile will shatter them]].

*** The Grenchlers. Way too much health (I swear those things don't take extra damage from the Dark Beam), obscenely damaging, will chase you into the water if you accidentally fall in (very easy in some of the rooms), plus they generally come in groups of three and have frighteningly broken hit detection. Oh yeah, don't even think about escaping to higher ground. They'll ''jump all the way up to you.'' And if you are at a distance, they will use an electricity based ranged attack. Alarmingly, going into the water is an even ''worse'' idea, even with the Gravity Boost, because they'll employ physics against you and electrocute the entire body of water you're submerged in.

*** Ingsmashers could count as well. Obscenely high amounts of health, high damage output in the form of hard-to-dodge attacks, and they have a shield that can only be destroyed using the Light or Dark Beam... which they bring up almost constantly throughout the fight. Not to mention that you're usually forced to fight ''two'' of them whenever they show up. While they can be killed instantly with a single Power Bomb, by the time you have Power Bombs you'll be using most (if not all) of them to progress through the game and find expansions, and since Power Bomb ammo drops are rare you're forced to choose between using one on an Ingsmasher or having enough Power Bombs to progress in the game. At the very least, Ingsmashers don't respawn like some of the other DemonicSpiders in the game.

* [[EliteMook Black Pirates]] from ''VideoGame/MetroidZeroMission'' are immune to every single type of attack other than the Plasma Beam, rendering the Screw Attack, Missiles, and Super Missiles that make Samus so powerful '''useless'''. Oh, and a pair of them wait right outside the endpoint of the final level, forcing you to beat them first. Many people find them more difficult than the FinalBoss. The only way to kill them easily is by abusing an AIBreaker.\\\
If the player is taking them on in a non-15% run, all he needs to kill them is just to rapidly hit the B Button, and dodge when necessary. On a 15%, one way to deal the most damage is to sit on a ledge and shoot them while they attempt to reach you.