Angel game

This is a game based on 2048 and inspired by Threes. Use the WASD keys to move the tiles. Some tiles can merge together and form a "higher" tile when they collide. Allowed merges are:

• 1+1=2, 2+2=4, 4+4=8...
• 1+2=3, 2+4=6, 3+6=9,...
• 1+3=4, 2+6=8, 3+9=12...

Easy mode adds the rule 1+8=9, 2+16=18, 3+24=27...

Every multiple of 3 is an Angel. The higher the power of 3 it is a multiple of, the higher of an Angel it is.