Sub-Zero is a 3-star base gold Arcane hero. A cryomancer capable of making endless copies of his opponents, he is a slippery and enduring combatant and a fearsome giant-killer when used well.
His shards can be obtained through Challenges.
Grandmaster of the Lin Kuei, Sub-Zero can create a clone of his opponent to fight for him in battle. Also, using an ice ball, he may freeze his opponent, stopping the victim's power generation and allowing for a follow-up attack from himself or one of his teammates.
Sub-Zero is incredibly powerful when facing opponents with much higher stats, particularly those with weak passives. His ice clone essentially steals almost all their stats for his use. In fact, his worst enemy is often the countdown timer, especially against high defence teams.
- Power generators/cost reducers: Doctor Fate, Power Girl or Emerald Green Lantern is good for him due to his power reliance. Doctor Fate is especially good because of his infinite 3-hit ranged combo than can pin down opponents without ranged specials. Normally this runs the risk of taking a supermove, but Sub-Zero can tank it with a clone.
- The Joker: Especially when facing extremely strong opponents, the combat capabilities of the third hero (other than Sub-Zero and Doctor Fate) becomes less relevant and The Joker can still be useful suicide-bombing with his passive, giving you 1 bar of power and stunning the opponent, giving you breathing room and vitally, interrupts specials that can normally deal multiple KO blows and would otherwise hit Sub-Zero.
- Heroes with strong effects that do not rely on their passives or supermoves.
- Heroes with Special block, such as Wonder Woman, Gorilla Grodd, Superman, and their variants. However, if special blocked, the ice clone will not freeze the target, reducing your time to react. Especially noticeable since using Klone Toss, like all specials, incur a global special cooldown - if Sub-Zero's opponent is not frozen, they can immediately use a special to KO the clone, and if you have the cooldown you can't block it with the clone's special block.
- Black Adam: His Electric Burst Ability still has a chance to steal power bars, and Lighting Cage can still activate the power cost reduction buff. Note that if Doctor Fate, Power Girl, or Black Adam are on Sub-Zero's team, they do not affect his clone, but if his clone copies an enemy Black Adam, the clone can activate its own power cost reduction buff that will apply to Sub-Zero and his team as well while it lasts.
- Soulstealer Doctor Fate: He may waste his supermove and passive against Sub-Zero's clone; as the clone is created at low health, Soulstealer Doctor Fate would likely damage himself and heal the clone, and if the clone has high defence it might even survive the super. His Break of Life is a very rare, if not the only, ability to be able to heal himself without involving his passive; therefore, Sub-Zero's clone can heal itself using it. However, the heal is very low and inefficient.
- Heroes with good specials that can deal multiple KO blows (so it could KO the clone and also hit Sub-Zero).
- Last Laugh The Joker: a clone being KO'ed will activate Joker's passive, giving him bonus damage.
- Horrific Scarecrow: Increases his power costs, which cripples his effectiveness.
- Justice League Batman: His passive allows all Justice League teammates to ignore one special, which prevents Sub-Zero from creating a clone.
- Armored Superman: Same as Justice League Batman, but he only ignores one special for himself.
- Black Adam: Same as Scarecrow, but more randomly from specials.