What's the best Android game for collecting and upgrading classic Transformers characters?

TRANSFORMERS: Earth Wars delivers a comprehensive character collection experience that spans multiple Transformers universes. The game includes bots from classic G1 series, Beast Wars, Headmasters, and Victory sagas, allowing players to assemble their dream team of Autobots or Decepticons. Each character features unique abilities and transformation sequences that stay true to their original designs. The upgrade system provides progression depth, though some users note that later upgrades require significant waiting times. Alliance features enable coordinated attacks with other players, adding strategic depth to the collection aspect. While the base interaction between characters could be more dynamic, the sheer variety of available Transformers makes this a standout for collectors. The game regularly updates with new characters and events, keeping the roster fresh for long-term players.