Oloro, Ageless Ascetic, gains its controller 2 life every turn it's in the command zone. Are there ANY other possible commanders that have abilities or benefits of being in the command zone or is he really the only one?
There are currently 6 other commanders that have abilities that function in the command zone. All of them were created for the preconstructed commander decks. They even eventually created the "Eminence" ability word for abilities that function in the command zone.
- Derevi, Empyrial Tactician has the ability ": Put Derevi onto the battlefield from the command zone." This lets you play the commander without casting it, so it cannot be countered as a spell (but as an activated ability, with Stifle) and avoids the commander tax* so it will always cost 4 mana.
- Arahbo, Roar of the World has the ability "Eminence — At the beginning of combat on your turn, if Arahbo, Roar of the World is in the command zone or on the battlefield, another target Cat you control gets +3/+3 until end of turn." giving you a free boost to one attacker each turn.
- Edgar Markov has the ability "Eminence — Whenever you cast another Vampire spell, if Edgar Markov is in the command zone or on the battlefield, create a 1/1 black Vampire creature token." giving you creature tokens for playing tribal vampires.
- Inalla, Archmage Ritualist has the ability "Eminence — Whenever another nontoken Wizard enters the battlefield under your control, if Inalla, Archmage Ritualist is in the command zone or on the battlefield, you may pay . If you do, create a token that's a copy of that Wizard. The token gains haste. Exile it at the beginning of the next end step." allowing you to get a token copy of your wizards for one turn, potentially triggering ETB effects or letting you use their tap abilities earlier.
- The Ur-Dragon - The Ur-Dragon has the ability "Eminence — As long as The Ur-Dragon is in the command zone or on the battlefield, other Dragon spells you cast cost less to cast." effectively making him a Dragonlord's Servant on or off the field.
- Yuriko, the Tiger's Shadow - Yuriko has "Commander Ninjutsu " functioning like ninjutsu from Kamigawa. This lets you bounce an unblocked attacker to put Yuriko into play. Like Derevi, this is not casting, so you will not pay commander tax.
There are also other cards that interact with the command zone, such as: Opal Palace, the Commander Storm cycle, Myth Unbound, all care about how many times your commander has been cast from the command zone. Palace adds that many +1/+1 counters to the commander, the Storms copy themselves that many times, and Myth Unbound cuts the commander tax in half.
Command Beacon moves your commander out of the command zone and into your hand, letting you ignore the commander tax and cast it like any other creature. Geode Golem lets you cast your commander by paying only the "commander tax" if any. And Reyhan, Last of the Abzan lets you put counters on creatures when another creature with counters dies or when it is returned to the command zone.
* This is the cost increase for casting your commander from the command zone again every time it is sent back to the command zone.
There are others, such as Derevi, Empyrial Tactician or any creature with "eminence".
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