Recently I found great mobile game. It’s called Horus Heresy: Legions and is available now only on Android as open beta.
The game is collectible card game (CCG) with famous Horus Heresy artworks. You can collect themed deck with one of the Legiones Astartes, also including there some Imperial Army, Mechanicum and Chaos cards.
Each deck is led by warlord with unique ability. By now you can play as Angron, Kharn, Mortarion, Tarviz, Fabius bile, Ehrlen, Kalas Typhon, Ingefel, Kelbor Hal, Calleb Decima, Loken, Abbadon, Horus and some other nice guys.
The game is made with great respect to background and lore of the Heresy. Each warlord and deck is played via unique mechanics.
You can check the game by yourself if you are on Android.