This character, faction, weapon, or otherwise isn't able to give everything they have from the word Go!, and needs to be worked up into a state where they're capable of doing their jobs beyond anything sub-par - if they're even capable of doing it at all before reaching said state.
This is not a case of voluntarily limiting oneself to avoid damage to oneself or one's surroundings — for whatever employs this trope, bringing their full might to bear from the get-go is just outright impossible. If you find this trope on an enemy, it will often have a distinctive sound accompanying it to serve as a non-verbal warning.
The reason for this varies, but Competitive Balance usually ensures that while anyone saddled with this downside takes their time to get going, once they do get going they are a force to be reckoned with. Sometimes this trope is binary, where something or someone has either gathered steam or not, sometimes it has multiple stages, and sometimes it is gradual and may not have any upper limit - in the latter case, expect them to eventually become just as much of (if not more than) a Juggernaut as a literal speeding locomotive usually implies - though if they can't handle their ever-increasing buildup they might eventually succumb to Over Heating and/or Explosive Overclocking.
Compare Magikarp Power which gives everything it has all the time; it's just that 'everything it has' starts out pathetic before repeated training, upgrades, or likewise makes it a force to be reckoned with. Compare Limit Break and Charged Attack which are powerful attacks or techniques which are only available after specific conditions are met and become unavailable again after having been used.
Contrast the Gradual Grinder, who probably isn't hitting harder in a prolonged engagement as much as they're making you less able to take what they've been hitting you with the entire time and the Pent-Up Power Peril which is the result of naturally building power needing an outlet every so often.
Usually has no relation to High-Pressure Emotion, but examples do exist where the act of gathering steam is correlated to an emotion.
The trope is ubiquitous in Real Life through inertia — nothing is able to perform at its best from the word 'go' unless it has been prepared in advance, and overcoming this trope quickly is essential in many fields. Super Trope to Increasingly Lethal Enemy and Sub-Trope to Situational Damage Attack
- In Bleach, Ikkaku's Empathic Weapon Houzukimaru slowly increases in spiritual power after it's unleashed in combat because, in his words, it's "lazy" and takes time to wake up all the way.
- Dragon Ball Super:
- Magetta is a bipedal living metal volcano whose magma heart grows hotter as fighting progresses. As his attacks draw on this heat for their effect, they grow more and more potent depending on how long he has been fighting.
- Ganos is a straighter example, with his powered up form gaining raw strength continuously. The speed at which he improves is based on the strength of the fighters around him (regardless of if they're friend or foe). When he's placed in the Tournament of Power, surrounding himself with the strongest combatants in every universe, his power increases so rapidly that Master Roshi can sense it climbing every second.
- This is Issei from High School DXD in a nutshell. Boosted Gear doubles his power every ten seconds without limit, however he has a dismal amount of Devil-power to start with and takes at least a few doublings before he gets going. He eventually learns to reduce the cooldown time with anger or focus, which makes him snowball even faster.
- Derrierie's special ability "Combo Star" in The Seven Deadly Sins allows her to increase the power of her hits by 2,000 pounds (or 100 tons) with every consecutive blows she deals on her target without interruption. Only a few people can survive over 50-hit combos from her.
- The Incredible Hulk. Bruce Banner is an ordinary human and needs to be pissed off to even trigger his transformation into the Incredible Hulk, but even once he has transformed, The Hulk is unable to bring his full strength to bear right away, as it is directly correlated to his anger. The angrier he gets, the stronger he gets, and thus with every injury he takes, he gathers more and more steam.
- Superman plays with this in certain continuities (such as the DC Animated Universe) as it actually seems that he starts out relatively weak and unlocks his power as the fight goes on. When explored, this is usually explained as having placed mental blocks, unconsciously, on his power to control himself after getting scared of his own strength, each block subconsciously unlocking as the need becomes clear. This trope is thus part of the reason you'll see Superman being tossed around a lot in the opening stages of a fight, even against inferior foes. note
- Max Damage in Irredeemable gradually gains power the longer he remains awake. When he wakes up, he has the power of a normal person, but after three all-nighters, he has the strength to go toe-to-toe with someone who can destroy countries in the blink of an eye. Of course, he tries to avoid staying awake for that long though, as his sleepiness would severely inhibit his judgment and reflexes.
- Back to the Future Part III: In order to get the Delorean time machine up to 88 miles per hour and return to the future, Marty and Doc 'borrow' a steam locomotive. In order to get the train moving fast enough, Doc powers it with homemade Presto Logs made to raise the boiler pressure and speed up the train. Each one is set to ignite in sequence, and by the time the third log ignites, the only way to stop the train would be to run out of tracks.
- In Fate/strange fake, Saber's Godspeed skill increases his Agility the longer a battle goes on. From an already respectable B rank, it can go up to EX rank if he keeps fighting long enough.
- Shadowrun supplement Street Samurai Catalog. The Vindicator minigun takes one combat turn for its barrels to get up to speed before it can fire.
- Champions. The Extra Time power limitation causes a power to take longer to activate. The longer the delay, the more the power's cost is decreased.
- In many Collectible Card Games, a resource is only accumulative at a fixed rate.
- Magic: The Gathering uses mana, which is generated by Land, you are, under normal circumstances, only allowed to play a single Land card per turn, and your most powerful spells might even take multiple combinations of multiple mana to perform.
- The Pokémon Trading Card Game limits you to playing one energy card per Pokemon per turn under normal circumstances, and although you can evolve your Pokemon without energy, their evolved forms usually require more than the unevolved form to attack, trading increased time to gather steam for greater power.
- Related examples are Pokémon with attacks that get stronger the more Energy is placed on them. Notable examples include Exeggutor from Jungle, whose Big Eggsplosion deals damage based on the number of heads flipped in coin tosses with the number of coin tosses equal to the number of Grass Energy on Exeggutor; and Ho-oh ex from EX Unseen Forces, whose Rainbow Burn does more damage the more types of Basic Energy are on it, and there are 9 types of Basic Energy.
- The Heavy of Team Fortress 2 has a variety of miniguns as options for his primary weapon. All of them have a need to be spun up before being able to fire at all. And catching a Heavy without his minigun spun up is usually a (relatively) easy opponent.
- Symmetra of Overwatch has a Photon Projector as her primary weapon. While it is able to do a Charge Attack, its primary mode of fire is a weak photon beam which intensifies as the connection is maintained, doubling the damage twice in discrete jumps if maintained for long enough.
- FTL: Faster Than Light has a number of weapons which combines this trope with Charged Attacknote . All of them having 'chain' somewhere in their name. The most notable example is the Chain Vulcan, a rotary-barrel laser gun. It starts out with an 11 second charge time per shot, with each shot lowering the charge time by two seconds. After five uninterrupted shots, totalling 35 seconds, it reaches its final state where it spews out lasers each second - singlehandedly overtaxing even the best shielded and most maneuverable ships quickly. It's Awesome, but Impractical in that most fights are usually over by that point, and any damage to the weapon will negate your progress and require you to spin it up again.
- RTS games in general have this as a necessity, obtaining the very best units and buildings often requires an arbitrarily long upgrade process. You can be safely assured that any faction with a relatively short upgrade process is meant to be rushing the opponent factions before their factions gathers too much steam for them to be beatable. In many cases, this is explained as needing to bring in specific off-map supplies (or constructing the buildings capable of producing them) which are needed to construct the best units.
- Depending on the patch, Starcraft II's Void Rays can be this. The very first version had them do more damage the longer they stayed on a single target by having their Converging-Stream Weapon use only one, then two, then all three beams (their damage increasing with each one), other patches instead give them a temporary damage bonus against Armored enemies. The versions seen in the single player campaign remain unchanged from the first patch, and so all have this trope built into them.
- Command & Conquer: Generals: Chinese Gatling guns (both the turrets and the Gatling tank) need to spin up before reaching maximum firing rate.
- Dawn of War: In the first game, there are several upgrades that exist solely to slow the player down, meant to represent Non-Entity General slowly escalating their engagement in response to other Non Entity Generals doing the same.
- Orks use a unique third resource that counts how many orks are present and requires a certain amount of orks present to build the more powerful units. This is meant to reflect the In-Universe growth of the Ork Ecosystem to the point it can support the more powerful Ork units - though Gork and Mork knows why it is needed for looted tanks.
- The Necrons' Greater Summoning Core is a building that produces and researches nothing, but is needed to get their final units.
- The Eldar, likewise, need to research upgrades which do absolutely nothing before they are able to field their more powerful units. Aptly named 'Mobilization For War' and 'Annihilate the Enemy'
- In Crusader Kings 2:
- Adventurers need a year to gather armies and ships, after they stated their conquest goals. Only afterwards can they launch the attack, so a smart ruler will try to assassinate them before they can do so.
- Similarly to adventurers, Viking invaders can state a conquest goal. Afterwards, soldiers and Viking heroes will join their cause over the next two years. They can attack at any time they want, but since their main targets are powerful Christian and Muslim kingdoms, they should better wait the full two years.
- The army size of nomads is dependent on their clan's population, which in turn is depending on the size of their territory. So a clan that just conquered a large kingdom will have to wait a couple of years so their population can grow so they can make use of their new land.
- In some way this applies to all conquests in the game. Getting a full duchy through a holy war is nice, but it will be utterly useless for the first few years, as the peasants will simply refuse to pay taxes or train as soldiers.
- In Grey Goo (2015), the human faction has access to the Lancer unit which fires a continuous laser beam, growing in power as it draws from more and more auxiliary batteries. This makes it incredibly potent against structures, and because the humans, as the game's Higher-Tech Species, have access to a six-unit teleporter, six lancers can show up in an undefended base instantaneously and turn it into a heap of molten slag before a defense can be mounted
- In Patapon your patapons will need some good rhythms to dance themselves into a frenzy, the amount of which depends on how on point they are. But once they are in fever they get much higher attack, reach, and/or other useful abilities depending on the class and on the dance.
- Vehicles in most Driving Games, just like in Real Life, require some time of acceleration to reach their top speed, and how fast they reach said top speed is often an important factor in Competitive Balance.
- Stardew Valley
- Plants that grow multiple crops without the need to replant them are this. Like every plant they need to grow to their full size first. But then they regrow their crops every couple of days, until they die at the end of their season (unless planted in a greenhouse, which makes them regrow forever, or if they are fruit trees that only become inactive out of season).
- Fruit trees produce crops with increasing quality the older the tree is. Bringing one up to iridium quality requires three in-game years.
- When a new animal is born, or bought from Marnie, it first needs to grow up before it can produce its goods.
- In Fallout 3 and Fallout: New Vegas, miniguns need a second or two of spinning up before they start firing.
- Several moves such as Fury Cutter and Ice Ball deal laughable damage at first but deal more damage if used consecutively (and have a less-than-stellar accuracy rate).
- Regigigas, the progenitor of Hoenn's golem trio is an Olympus Mon with stats on par with the Elemental Embodiment of the oceans and the core's magma, both of which wreak havoc on the weather by merely being awake. Regigigas has been stated in legends to be capable of moving entire continents, but when it is encountered it has slumbered for so long that it takes a while to shake off the rust and moss growing on it, which is reflected in its ability 'Slow Start'; For the first five turns of combat its attack and speed stats are cut in half, which puts it straight into Awesome, but Impractical for battling wild Pokémon because most fights are over by then. Of course, capturing it is likely to take more than five turns, and its defensive stats being unaffected means that a well-informed player can use him as a wall until the steam is gathered.
- Also falling into this trope are Abilities such as Speed Boost, which causes the user's Speed to increase at the end of each turn; and Moody, which causes one random stat to decrease slightly but another random stat to increase sharply. To a lesser extent are Abilities like Moxie, Soul-Heart, and Beast Boost, which grant stat boosts each time they deal a knockout. Pokémon with these Abilities can quickly become unmanageable if left alone for too long.
- Like with Collectible Card Games, their electronic equivalent, the Card Battle Game also has instances of accumulating resources at a maximum fixed rate.
- Hearthstone has mana, which accumulates at one crystal per turn until a maximum of 10 is reached. Druids have ways to accumulate this faster through the use of specific cards.
- Emperor Tharuissian is a card which reduces the cost to play any cards in your hand by 1 each turn he is in play, effectively reducing the time needed to gather enough steam to play those cards.
- Plants vs. Zombies: Heroes uses a similar mana system to Hearthstone, where the Plant and Zombie players get one extra sun/brains per turn with no cap limit. There also exist Plant and Zombie Teammates that buff themselves or other units every turn or when a card is drawn (which happens at the start of each turn) — Team Mascot gives all Sports Zombies including itself +1/+1 each turn, Doubled Mint's stats double each turn, Bananasaurus Rex and Tricarrotops get +1/+1 when a card is drawn, Stompadon gives cards in the Zombie player's hand +1/+1 when a card is drawn, etc.
- Hearthstone has mana, which accumulates at one crystal per turn until a maximum of 10 is reached. Druids have ways to accumulate this faster through the use of specific cards.
- Elsword contains "buff stacking" passive skills for certain character classes which makes the character stronger the more they hit enemies.
- As a Sheath Knight, Elsword's Cruel Slayer passive gives him additional damage buff that occurs and stacks per 5 hits he does in a normal combo and active skills. The additional damage he can gain is (depending on the passive skill's level) 2% to 10% of his physical attack power, and it can be stacked 5 times. If he spent 10 seconds without adding to the stack (i.e not hitting 5 times), the buff will be gone and he'd need to build it up again.
- Crimson Rose's Awakening Will passive can activate a special buff that occurs if she uses skills related to chain attacks. Each hit of chain attacks will accumulatively buff her physical attack power and attack speed, up to 25 stacks. The buff stacks will lose by 5 every 3 seconds she isn't attacking with any chain attack, however.
- Zul'jin of Heroes of the Storm is a downplayed example. While he is no slouch in combat normally, he has a popular early talent which increases his attack speed by 6% every time he kills an enemy, stacking up to five times for a short duration and refreshed with every attack he makes, making him at home in prolonged engagements. Kill him quickly before he has a chance to kill anything and he won't be capable of even gathering steam before he dies. Just be careful of his Taz'Dingo! Heroic, which is dangerous for an altogether different reason.
- Devil May Cry 4: Nero's sword has the "Exceed" system which combines this trope with Charged Attack; he "revs" the sword's handle which charges up heat energy into the sword; there are 3 units of it in the Exceed meter. If the meter is filled, each of his sword's normal combo strikes will become stronger as they consume one unit per strike, and his special moves with the sword consumes all of the meter. The unique part is how the meter is gained: he can normally rev it (just like how Gatling guns spin up first) to fill the meter, but to fill each unit, the "rev" button must be pressed 3-4 times; it becomes tedious quickly to always rev it before you attack. But, he can also rev it during his sword strikes - called Ex-Act - and doing so will automatically give him one full unit that is immediately spent, making the strike immediately powerful; this can be done in normal sword combo attacks as well as special sword attacks. Even better, if he revs it during a specific frame of each sword strikes - called Max-Act - he will instantly gain 3 units (i.e full meter) with each swing, with one unit immediately being used.
- The Razor Claws are a pair of energy blade that increases in power and gradually turns red every time Ratchet hits an enemy with in Ratchet & Clank Future: Tools of Destruction. However, it will reset when Ratchet takes damage.
- The Revenant in Nexus Clash has a Blood Frenzy that adds massive stacking bonuses for each subsequent kill in battle, at the price of making them even more of a Glass Cannon in a way that also stacks. It's possible for a fully-charged Revenant to be a violent buzzsaw of utter destruction capable of wiping out entire strongholds, but who can get killed in a few shots if anyone can actually score a hit on them.
- Dead by Daylight: Michael Myers begins a match with low movement speed. Keeping an eye on survivors and stalking them allows him to level up to Evil Within 2, buffing his speed and lunge range. Filling the meter to Evil Within 3 gives him sixty seconds of double damage, knocking healthy survivors to the ground in one hit.
- Certain killer perks have this effect, as well. Freddy Krueger's "Fire Up" boosts the killer's action speeds as the survivors fix generators. Fully upgraded, the Hag's "Devour Hope" grants double damage after three survivors have been rescued off the hooks, and lets the killer execute downed survivors after five rescues. Every time a survivor gets put on a hook, "Huntress' Lullaby" further decreases the advance warning survivors get before a quicktime event, making them more likely to fail and set back their progress.
- Borderlands 2 features two different takes on "stacking" mechanics with its DLC characters:
- Gaige's Ordered Chaos skill tree focuses on Anarchy, which you gain by either killing an opponent or emptying your gun's magazine in combat. Each stack of Anarchy increases damage but decreases accuracy (which can be mitigated with her Close Enough skill), so that eventually every shot will be flying wild across the area but the ones that land will hit like a Mack truck.
- Krieg's Bloodlust skill tree focuses on building up stacks of Bloodlust by damaging opponents, which confer various bonuses the more you have but decay quickly once you stop damaging opponents, incentivizing a Bloodlust-focused Psycho not only to build pressure but to keep the pressure on as well.
- Saryn's spores are like this. The more enemies they afflict, the more damage they do, until they can kill every enemy on screen in seconds. In fact, this is their biggest weakness, as once Saryn runs out of enemies her spores quickly decay and she's back to square one.
- Nidus is similar, but slower and longer-lasting. Every time he hits an enemy with Virulence, he gets one-sixth of a Mutation stack. For every stack of Mutation, Virulence's damage increases, as does his health regeneration. By gathering large numbers of enemies together and hitting them all at once, he can build Mutagen very quickly and become The Juggernaut. His Mutation stacks don't decay unless he dies, wanders into an Anti-Magic field, or spends them on powerful abilities, making him great for long missions.
- Lung from Worm is a parahuman who on top of his pyrokinesis and Healing Factor, mutates as a battle goes forward, growing larger, gaining scales, and even growing wings as long the battle continues and there's people watching, as well as an increased proficiency with his pyrokinesis and healing. Word of God is that he has no true upper limit, and at the highest level witnessed in the story, he manages to beat back Leviathan, one of the Endbringers, when he flooded Kyushu, only stopping when he notices pretty much everyone else is dead and therefore can't witness the fight.