Twenty-Can you get to 20?

This is a fascinating solo puzzle game.

Starting from 1, you need to tap at least two of the same numbers to merge them into a bigger number. For example, two or more 1 merge into 2.

Piece of cake, huh? As simple as it sounds, you need to strain every nerve to play it well. Few people can actually make it to 20, as far as we know.

So can you make it to 20?
Play with your friends and find out who is the best!