The Land Of OverJoy: I don't play much piano, but if that is playable it sure has to be fun, very dreamy vibes :D
OverKill: I loved this one, you captured very well the marching of the soldiers and also the dissonance makes it very nightmarish. (I don't know why but it reminded a bit of the Magia Record OST or the witches' themes from Madoka Magica)
I would have liked a longer version of OverKill but overall good job with everything!