One of my primary sources of motivation for Outcasts is its four different endings and what events determine the ending you get, which all ultimately depends on a few important choices. Not a very complex system, I know, but I think it'll work out nicely.
In a more technical sense, I really like the game's battle system. It functions somewhere between Undertale and basic platformer combat like Shovel Knight and the like, and it's more about being strategic with your limits rather than having an entire move set at your disposal.
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