Commander Masters, while primarily focused on reprints, gave us a handful of new cards in each Commander deck. As expected, most of the cards, new and old, from the Eldrazi Unbound Commander deck are focused on enormous colorless haymakers. The primary Commander,
Zhulodok, Void Gorger

What’s interesting, though, is that the secondary Commander is very different.
Omarthis, Ghostfire Initiate

Whenever you put one or more +1/+1 counters on another colorless creature, you may put a +1/+1 counter on Omarthis.
When Omarthis dies, manifest a number of cards from the top of your library equal to the number of counters on it.
does cost double x and is colorless, so it still works reasonably well with Zhulodok and the big colorless Creature theme. It even has the ability to Manifest a bunch of cards, and some enormous Eldrazi can then be turned face-up later if you are lucky.
The thing is, there’s a lot more synergy that can be had with Omarthis. This is especially true with its second clause that dictates that Omarthis gets additional counters every time another one of your colorless Creatures does. There’s a lot of ways to abuse this ability beyond what the Eldrazi Unbound deck has to offer.
Lots of Triggers for Omarthis

Luckily, the ability of Omarthis to gain additional plus-one plus-one counters is not capped to trigger only once each turn. This means that colorless Creatures you control that can gain additional plus-one plus-one counters each turn cycle can continue to grow Omarthis. Cards like
Hangarback Walker

When this creature dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on this creature.
{1}, {T}: Put a +1/+1 counter on this creature.
and
Walking Ballista

{4}: Put a +1/+1 counter on this creature.
Remove a +1/+1 counter from this creature: It deals 1 damage to any target.
are excellent additions to an Omarthis Commander deck. Not only does Omarthis get counters when Hangarback or Ballista are cast, but it also gets counters whenever you activate Hangarback’s or Ballista’s abilities. Ballista in particular doesn’t need to tap to activate, meaning if you have enough mana, you can generate multiple counters for Ballista, and therefore multiple counters for Omarthis.
Omarthis can really go crazy when you have ways to get a bunch of counters on other colorless Creatures you control that don’t require tapping them or investing lots of mana. Think of a card like
Arcbound Ravager

Modular 1 (This creature enters with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
. Every time you sacrifice an Artifact, both Arcbound Ravager and Omarthis grow. It’s important to note that you can’t use Modular to put additional counters on Omarthis, since it’s not an Artifact Creature. Still, if you have a lot of expendable Artifacts available, using Arcbound Ravager’s ability to keep growing Omarthis can be very powerful.
Similarly, if you have
Patchwork Automaton

Whenever you cast an artifact spell, put a +1/+1 counter on this creature.
in play, every time you play an Artifact to trigger Patchwork Automaton, Omarthis will get a counter too. Omarthis does say that you get one counter on Omarthis if one or more counters are put on another colorless Creature, so putting multiple counters at once on another colorless Creature won’t benefit Omarthis quite as heavily. However, individual triggers from Patchwork Automaton work perfectly.
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Going Above and Beyond

To maximize Omarthis and make sure it doesn’t get exiled, which would prevent you from getting to Manifest a ton of cards from your library, it might be worth utilizing a beneficial Sacrifice outlet to guarantee you get your value. Cards like
Ashnod’s Altar


At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.
.
The Ozolith helps gaurantee that other Creatures you control with counters on them that die don’t go to waste. With a sacrifice outlet, however, you can decide to put a bunch of counters from another Creature like Hangarback Walker onto the Ozolith, then move all of those counters onto Omarthis. From there, you can convert Omarthis into a ton of Manifest Creatures at any point. The choice is yours.
Beyond the Ozolith, there are still lots of ways to put lots of counters on Omarthis at once. Assuming you have a bunch of Artifact Creatures in play,
Steel Overseer


Going Even Further

If Omarthis is not your Commander, that opens the door for you to go even bigger. If you pair Omarthis with Spark Double, you can copy Omarthis, and Spark Double won’t die because it enters with an additional counter on it. Not only that, but much like with
Botanical Brawler

This creature enters with two +1/+1 counters on it.
Whenever one or more +1/+1 counters are put on another permanent you control, if it's the first time +1/+1 counters have been put on that permanent this turn, put a +1/+1 counter on this creature.
, Spark Double entering with the counter should cause the other copy of Omarthis to trigger (of course, triggering Omarthis is relatively trivial anyway if built around correctly).
When the counter is added to the original copy of Omarthis, this will trigger the Spark Double copy. This causes a chain reaction, where both copies can grow “infinitely” large. Luckily, putting a counter on Omarthis is not required, so the game will not end in a draw. Be careful though, if one of your Omarthis copies dies, you will end up Manifesting a lot of cards, so make sure not to lose via decking! Given that the main payoff being for Omarthis is that you get a ton of Manifest Creatures, it’s important to maximize these Creatures that Omarthis generates when it dies.
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Maximizing Manifest

Omarthis pays you off for growing it by allowing you to Manifest a number of cards from the top of your library equal to the number of counters on it. Not only does this ability benefit from Omarthis having lots of counters, but it also benefits from ways to abuse Manifest Creatures. Manifest Creatures don’t have specific Creature types, so using a card like
Coat of Arms


At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice this artifact.
can be incredibly useful at both protecting your army against board wipes and giving your squad a buff and evasion. With hopefully tons of Creatures in play, sacrificing one at the beginning of your upkeep shouldn’t be a big cost.
Another excellent addition is
Forsaken Monument

Whenever you tap a permanent for {C}, add an additional {C}.
Whenever you cast a colorless spell, you gain 2 life.
. Forsaken Monument not only provides a buff to all your Colorless Creatures, which includes Manifest Creatures, but it also allows your colorless mana sources to give you additional mana. With Omarthis as a Commander, you can never have too much mana. In addition to buffing your Manifest team, there are other ways to benefit from your freshly made army.
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Beyond a Buff

Manifest Creatures naturally have the ability to be turned face up for their mana value, so long as they are Creatures. The downside is that this often requires a lot of mana investment, and cards like Hangarback Walker that are face-down don’t really benefit from being turned face-up, since they won’t have counters on them. You also don’t get to turn non-Creature spells face up, meaning important cards like the Monuments may be lost forever. Well, this is assuming you can’t find a loophole. Luckily, cards like
Conjurer’s Closet

Omarthis has a lot more going for it than may appear at first glance in the Zhulodok Commander deck. It’s totally fine at face value but can be heavily abused as a Commander itself. If you are looking for a unique colorless Commander option, Omarthis might be perfect for you.
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