[mdaniel]

I think I am not following some nuance; given:

  4 4 2 16
  8 8 4 2

pulling that 4 up into its friends yields

  ? ? 8 16
  8 8 2 2

which after seeing that behavior across several combinations (2 2 2 -> 4) I'm now guessing the actual rules are "The more tiles in the match, the higher the resulting tile will be, PROVIDED IT IS A POWER OF 2". So, one must join at least 3, but only the power-of-2 pairs count, the other tile just evaporates

[MikeBellika]

I’m not a 100% sure i follow but i’ll try to explain. The tiles can only be powers of two. Matching 3 tiles will make the matching tile the next power of two. So 2-2-2 will make 4, 4-4-4 will make 8, 8-8-8 will make 16, etc. If you match more tiles, it will go to higher powers of two. 2-2-2-2 will make 8, 2-2-2-2-2 will make 16. Only one tile per match will be turned into the higher tile. When swapping a tile this will be the swapped tile. When part of a combo, it will be the tile with most matches. If multiple tiles have the same amount of matches it will be the left/top most tile. The other tiles do indeed “evaporate”. I hope this makes some sense, wrote it from my phone.