/agdg/ - Amateur Game Development General

CoC already has 15+ clones on the android store, don't think you have a problem even if you tried to make money off it.

Cloning something that exists is universally considered good practice, as long as you don't pretend that you came up with the concept. Make it open source and you'll be 100% in the clear (though you'll be fine even if you don't).

Everybody's first few forays into game programming are clones of some sort, and nobody has ever been criticized for it by anybody important.

Just make sure you change the art, names, and values (damage, HP, etc.). Gameplay isn't copyrightable, but certain elements of a game are.

If you want people to play it, do something to make it not just a clone. There are a lot of ways you could improve on CoC.

Remember to post full game name at least once. Initially I thought you want to dabble in Corruption of Champions.

Anyways, if it's just for practice, there's literally no reason not to.

Idk about releasing such a game, but making a clone is a fantastic learning method. You have a perfect reference to see if you're doing well, you don't have to come up with anything, you just face one technical challenge after another.