The Binding of Isaac (2011)

cat anthropomorphism murder bloody drugs death steam achievements revenge easter egg nudity boss fight explosion steam achievements digital distribution playing cards voice acting protagonist's name in the title bow and arrow original soundtrack release wasd movement downloadable content melee a.i. companion difficulty level destructible environment evolving title screen suicide game with chapters ambient music flashback male protagonist ghosts action-adventure darkness single-player only magic retail games with steam activation instant kill non-player character black market female antagonist bird steam trading cards summoning support traps shopping status effects wizards permadeath throwing weapons upgradeable weapons multiple endings severed limbs vampirism robots extreme violence christianity gambling pop culture reference descendants of other characters self-referential humor movie reference boss assistance poisoning giant insects white noise young protagonist secret area vision obstruction video game characters that play video games valuable garbage context sensitive hidden room slot machine alternate costumes internet culture reference point of no return multiple protagonists treasure chest horse religion teleportation silent protagonist swarming enemies foreshadowing unlockables developer cameo temporary invincibility multiple enemy boss fights worm spider procedural generation cameo appearance cross-dressing aggressive door-opening monsters infinite ammo fake glitch bats gods challenges steam play based on - book optional boss dice humble bundle super speed deliberately retro roguelike resized enemy multi-phase boss hidden character monsters that look suspiciously like genitalia dungeon crawler passive ability air strike transforming boss consolation achievements ouija board single-screen level distaff counterpart trail of death conga line party child protagonist flash game origin bullet hell roguelite