A 3/3 creature on a player's second turn makes for exciting gameplay
Once Kuja doubles the damage your Wizards do, this new instant could be a way to just take a player out at any point
As such, the average game plan for Defender Tribal involves playing the best creatures of anyone on the board, mana for mana value
Sure, three mana Pacifisms dont really cut it these days, but this can shut down Escape creatures and enable enchantment bonuses
Much of Kruam's appeal is simply that it gives you access to blue and red in your commander deck, letting you have access to practically all the best colors in the game (sorry green)
A slight sliver of hope remains for those who face her, because when she leaves the battlefield, her owner gets board wiped