His -7 won't break the game or anything, but digging 10 to draw three is a lot of cards, and considering it should be fairly easy to keep looping the ultimate by using it, attacking next turn with an air force, then ultimating again, he should draw us a lot of cards over the course of his life
You can basically count Land Tax as a mana source since its quite convenient to have it while youre mana screwed
The road to hell is paved with good intentions
Magic players know this as Summoning Sickness
Personally I'd play it safe and look to move my copies while prices are high
Creature - Dragon Color tag templates(None) Hooting Mandrills Delve (Each card you exile from your graveyard while casting this spell pays for .) Trample Creature - Ape Color tag templates(None) Jaheira, Friend of the Forest Tokens you control have " : Add ." Choose a Background (You can have a Background as a second commander.) Legendary Creature - Human Elf Druid Color tag templates(None) Kird Ape This creature gets +1/+2 as long as you control a Forest