History Main / CastFromHitPoints

* In the universe of VideoGame/{{Guenevere}}, dark magic works this way; it is physically exhausting to the user if they don't have an external source of power.

* In the WebSerialNovel ''Literature/{{Katalepsis}}'', Heather has the ability to use a ... ''sideways'' form of mathematics to effect changes to the world around her and even herself -- magic by any other name, as it were -- but it hurts her badly. It ''starts'' with the PsychicNosebleed, goes on to massive bruising and contusions, then continues from there. While she typically bounces back fast for various reasons, it still leaves her in a critical state as often as not.

* In ''VideoGame//VocaloidNoNatsuyasumiFinalFourDays'', Miku learn [ShockAndAwe Electro] at level 18, which cost 5 HP instead of her MP. This attack doesn't deal much damage to most enemies, but against mechanical target (including most bosses), it deals 3x of her base attack, the highest multiplier in the game.

* Most games in the ''VideoGame/{{Atelier}}'' series use this system, with special attacks costing a percentage of a character's HP to use. The UpdatedRerelease of ''VideoGame/{{Atelier Rorona|TheAlchemistOfArland}}'' drops this in favor of a standard HP/MP pool.

* In ''VideoGame/FZero X'' and GX/AX, {{Nitro Boost}}s can be activated at any time after the first lap but drain your vehicle's life meter when used.

** [[VideoGame/TheLegendOfHeroesKuroNoKiseki Aaron Wei]] also has a Craft that decreases his HP, but unlike the above examples, it doesn't give him CP. Instead, it grants him other bonuses, such as Insight.

* ''VideoGame/CorruptionOfChampions'' has two sets of magic armor -- the Inquisitor's Robes and its DistaffCounterpart the Inquisitor's Corset -- that, when worn, change the spellcasting mechanics by using HP instead of Fatigue points to cast spells and activate mental and supernatural specials. These armors can only be found in the swamp and take a ridiculous amount of searching to find, and you can't obtain both sets with the same character, but for a mage or MagicKnight, they're considered the best light armor sets in the game. It would definitely be worth your time to search the swamp until you find them if using magic figures heavily into your core skill set, especially if you have a high Toughness score and all of the Tank and Regeneration perks.

** The Fire Vellumental's main attack involves it scattering its burning feathers over the battefield to create obstacles. It depletes a little bit of its health bar every time this happens, meaning that after a few rounds of this, the Fire Vellumental will have slowly [[JustForPun burned]] away its HP.

** How powerful can a ninja be when all Eight Gates are open? Powerful enough to be able to curbstomp a PhysicalGod. Demonstrated when Guy performed this technique and went to wipe the floor with Madara, who at that time was the Ten-Tails host and was previously curb-stomping the most powerful ninjas in the world. Guy even gets complimented by Madara for being the first one to actually give him a challenge, but points out that it would only be a matter of time before Guy's technique ends and all Madara has to do is wait it out since it didn't (or couldn't, anyway) kill him. Madara was using Perfect Susano'o, said to be impenetrable. ''Guy's final attack shattered it''. Madara's only saving grace was being undead and thus having unlimited chakra with which to replenish his Susano'o. Said technique was mastered by Might Dai, Guy's own father. How strong was he with it? Enough to where he was able to go toe-to-toe with ''all Seven Swordsmen of the Mist'' at the same time in order to save his son and his comrades. While the battle did take his life, he manages to kill ''four of the Swordsmen'' and left the other three severely beaten.

* Occurs more than a few times in the ''VideoGame/SonicTheHedgehog'' series. In ''VideoGame/SonicBattle'', Chaos Gamma has the Power move Meltdown that causes horrific amounts of pain, but also takes a big bite out of his health bar. There is also the various [[SuperMode Super Forms]] that a handful of characters can take, which typically absorbs one ring per second from a minimum of fifty. If all the rings on hand are consumed by this form, then the character is left either as a OneHitpointWonder or, in later games, dead from exposure to deadly environments such as [[BatmanCanBreatheInSpace the vacuum of]] [[SubvertedTrope space]] or [[SuperDrowningSkills the flooded ruins of a city.]]

* ''VideoGame/TheLegendOfZeldaMajorasMask'': The Blast Mask provides Link with a limitless supply of bombs with the catch that each one causes damage. Raising your shield, however, will prevent the damage even though the source of the explosions is ''strapped to your face!''[[note]]The explosion is placed a short distance in front of the mask, just slightly farther out than Link holds his shield, allowing it to block the blast. Still strange, as the shield should reflect more of the explosion back towards Link.[[/note]]

* The Life Leech from ''VideoGame/{{Blood}}'' normally uses trapped souls as ammunition; if you run out of those, it uses your HP as ammo instead. It's really a non-issue, considering it drains health from any enemy it hits and adds it to your own.

** For the most part, whenever a card effect in the card game requires a cost to activate, it's generally one of two things: a discard from your hand or deck or a payment of life points. Considering that the loss of either resource in their entirety means game over for you, this is very much a Cast from Hit Points scenario. The third is typically the sacrifice of a monster, which also fits, even if it's not ''your'' hit points you're using.
** The Lightsworn-archetype Deck uses the first type, as several of the monsters and spell/trap cards discard two to three cards from the top of your deck after activation or at the end of every turn. The recently added Psychic-type monsters normally drain Life Points to use their effects, but there are also a few that give some back.