Monster Sanctuary would melt his brain. It's essentially pokemon but it's always 3v3 (once you have at least 3 monsters) and while you heal between battles the normal mode has had complaints of being too hard for casual players, resulting in a patch that included a lower (and higher) difficulty.
So, 0utsider would have less filler (no pokemon centers, failing a battle puts you right behind where you died), Phil would be confused because it's a metroidvania (despite there being a map), and it could be like D : OS2 because the game itself thrives on monster synergy (for example, some creatures have a strategy based on charge stacks to increase damage, others status effects, others still rely on tribes which require reading the in game monster manual). It's also on console so he has no excuse to avoid it. All in all sounds like it'd at least one ragequit not-having-fun-quit with minimum a pinch of salt, maybe more if he does online battles.