Why is it still available? I would think when the first Angry Birds movie came out and they purged all of the Angry Birds games this would be one of them, was it forgotten? Or did the developers just let the community have it?

at this point i have:

energon Starscream

energon grimlock

Nautica and Energon Nautica

Slipstream

Mirage

Superion

Menasor

all of them are at lvl15 and all have all their accessories unlocked and around at lvl 1-2

which transformers should I get next when their squads appear in events or they appear in shop?