What is Valley 2? It's basically a Metroidvania game mashed up with a turn-based strategy game. This is sort of the spiritual successor to the old SNES game Actraiser in some ways, and in other ways there's just not anything else out there like this - not even AVWW1.
On the combat side, things are more visceral and tactile this time around. Spells have mass and can block each other, and the way enemies are designed and placed has been re-thought from the ground up.
If you've already bought AVWW1, you get this game free. If you buy these in the future, you get both for the price of one.