The Battle's protector is not its controller, he is just the player assigned to defend it, the player who casts the Battle is its controller
If you play a lot of constructed Commander, these decks arent any more complicated than player constructed decks, but theres a lot of triggered/activated abilities, +1/+1 counters, and various mechanics from all over Magic inside them
Chucking a land into the graveyard is easily exploitable by cards like Wrenn and Six or Crucible of Worlds, which lands-based decks are already interested in playing
Round 5 vs Whitebeard Whitebeard is an easy match up since they need to play the 9cost whitebeard the turn before Nika if they do not, they die easily
Grim Flayer also probably has to go
One of the most exciting examples is Tifa Lockhart, a green two drop with some seriously explosive potential