Between the counter distribution on ETB and the general benefits of being in green, we should have no trouble maintaining the largest creature
5 Tarkir Clan-themed dice (1 Temur d20, 1 SUltai d10, 1 Azban d10, 1 Mardu d6, and 1 Jeskai d6)
There are choices to be made, and rewards to be won, and it's a neat addition, if somewhat gimmicky
Obvious contenders are Snapcaster Mage and the like - creatures that accrue their value when entering the battlefield or in response to an opponent's attempt at a maneuver, and can then be used to counter a new threat later
While this card will be an auto-include in my Sakashima the Impostor Commander deck, I'm also excited to see it played in Zendikar Rising Limited, where it potentially ends up as a dual-class party member, a copy of a massive creature you already control, or even a land drop when you really need it