If you have 10 creatures all with 3 power, you don't have a "coven" because they all share the same power
For example, if you attack with a creature that is equipped with Acquisition Octopus, then use reconfigure to unattach Acquisition Octopus after combat, the Octopus will be untapped and could be used to block during your opponent's turn
Partner (You can have two commanders if both have partner.) Legendary Creature - Human Artificer Phyrexian Sardian Avenger First strike, trample Whenever this creature attacks, it gets +X/+0 until end of turn, where X is the number of artifacts your opponents control
This 2016 Pokemon Center exclusive comes from the Mario Pikachu collaboration campaign
It has a high buy-in but Gaeas Cradle shows us how high it could theoretically get (not that a card that is multiples in Legacy is comparable in demand to an EDH card, though there are fewer Sanctums than Cradles)