Best counter to London?

It depends on what you play against moves like 1.d4 and 1.Nf3
If you don't really care, then at low rating a KID setup is usually pretty nice because the pawn on d6 keeps a knight out of e5, which is pretty much the only thing low rated London players know how to do (put a knight on e5 and hope some kind of kingside attack works out).

Oops, when I google "kid chess" the opening doesn't come up of course.
kid is king's indian defense. So something like this for example:
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