Still a lot unguessed, so some more hints:
#27: Resident Evil: Revelations guessed by S.Peelman
#26: Armello guessed by Jpcc86
The king is consumed by the rot.
The king is a lion.
#25: Jagged Alliance guessed by Darashiva
"Хорошо! Я буду работать на тeбя, проклятый капиталист!"
Mercenaries are a bunch of drama queens.
#24: Fire Emblem: Radiant Dawn guessed by Jpcc86
Silver haired maiden.
Dawn brigade.
#23: Return to Zork guessed by UnderwaterFunktown
#22: UFO: Enemy Unknown/X-COM: UFO Defense guessed by Jpcc86
Elirium 115, the first game.
Cyberdiscs, Reapers, Snakemen.
#21
What caused the hollowborn?
Maybe killing a god?