Good amount of Tris for a mobile game? What would be a good amount of tris for a character that will be used in a mobile game? So you have an idea lets say a mobile game like Clash Royale, I'm of course trying to keep it low but I just wanted to know what is actually a good amount.
As much as necessary but as few as possible :)

The goal is to have a playable performance. And this depends on too much factors like shaders, draw calls, how much geometry at once, rest of ongoing code, target platform, target OS, and and and. The geometry is usually the smallest problem nowadays. The common graphical resource hogs are draw calls, particle systems, shadows. But code can slow down the game dramatically too.

That's why you normally start with a prototype to figure out what is possible within the given bounds. So make a prototype and simply try it out.