2048 Rare Birds

It's 2048, but the tiles are birds... and they sing. Slide two of the same bird together and they merge into the next, rarer one up the ladder… and you hear it: a real recording of that bird's call. A little Spotted Pardalote becomes a Ruby-crowned Kinglet becomes a Splendid Fairywren… all the way up to a Hoopoe (that's your 2048), and if you're good, a Kea and a Superb Lyrebird.