If you had to do a mouse only challenge(no keyboard), which champion would be the most viable?

You have to play the game with only your mouse and no keyboard. However, you are allowed to keybind skills to your mouse such as "mouse button 3", "scroll up", "scroll down"....etc...

What champions would be the most viable in this challenge. ADCs were the first ones to come to mind, however, I also felt they are not due to how important their skills are to them. Someone suggested Singed, but I might be hard to do without fling or item active.

In your opinion, which champion is the most viable?

Forgot to mention: Although you don't have a keyboard, you can still left click your skills in game and click somewhere else to use them.