Dawn of Sorrow (2005), the first installment of Castlevania on Nintendo DS, is a direct sequel to GBA hit Aria of Sorrow. Everyone is trying to kill our hero Soma Cruz, since in the previous game he absorbed all of Dracula's attributes. Leave it to weird cults to try and bring about the end of the world by unleashing this power.
The game is so fully broken at this point that there really is no plot in this run. Or final boss. Or much of anything at all. Using movement optimizations and a new zip, this movie completes the game 00:19.34 seconds faster than its predecessor. More details about the glitches can be found in the author's comments.
To play back the DSM file, make sure that "Enable Advanced Bus-Level Timing" and "Use dynamic recomplier" are unchecked in the "Emulation settings".