Commander Commander (CTRL to add secondary) Cards to remove Cards to remove (CTRL to add secondary) Draw Wheel of Potential You get (three energy counters), then you may pay any amount of
That means that if it's just you and one other player in the game, you'll have to target yourself when that player casts their first spell each turn
Commander Masters addressed that directly
When Brinelin, the Moon Kraken enters the battlefield or whenever you cast a spell with converted mana cost 6 or greater, you may return target nonland permanent to its owners hand.Partner (You can have two commanders if both have partner.)
Imagine your foe controls a dork that will shut you down
Still, it's cool that a druid's main capability being able to shapeshift is well represented here, albeit in a mechanic that definitely isn't how it works in Dungeon's & Dragons