Marvel Mystic Mayhem Act 3 bosses at nightmares are brutal, going through different phases at a rapid pace, inflicting stagger damages on a colossal scale, and they offer little room for error. In order to clear them, players will have to rely on high-damage single-target DPS. Here’s the line-up of the best-performing heroes that players may count on.
Best Hero Combos for Act 3 Nightmare Bosses
High-Stagger, High-DPS Combo
Psylocke (Striker) – She is best at quickly shattering stagger bars. Her ultimate explodes psychic marks, which causes a huge burst on single targets.

Cyclops or Cable (Beam DPS) – Either will suffice here. Cyclops offers consistent beam damage, and Cable is a sustained DPS, especially with energy feeders.

Moon Girl & Devil Dinosaur (Energy Buffer) – Her EP regen ability is indispensable in long boss fights. She makes sure the Ultimates never stop coming for the whole team.

Beam-Focused Burst Damage Setup
Iron Man (Striker) – His Repulsor Beam synergy provides high burst single-target, particularly boosted by Unibeam and Iron Legion ult.

Scarlet Witch (Striker) – Although most of her damage is AOE, she can do huge bursts on bosses if paired with cooldown synergies and focuses, especially with cooldown buffers.

Misty Knight (Striker) – Quick ranged DPS with linear ultimate; excels at focused boss damage.

Melee Pressure with Control Combo
Black Knight (Striker/Fighter) – His primary attacks possess high single-target burst, and a revive once passive for better survival.

Hulk (Defender) – Although classified as a tank, his combos stun and deliver good sustained damage; ideal for prolonged boss fighting.

Storm (Controller) – Provides primary crowd control, slows, stuns, or AoE damage, to open stagger windows for melee DPS.

Pro Tips for Survival through Act 3 Nightmares
Energy is everything – Without Phoenix or other EP regen, your damage uptime suffers.
Stagger first, damage second – High damage output stagger teams have huge damage windows.
Synergies trump raw stats – Storm slow, Wasp whirlwind, or Wolverine’s self-buffs can turn fights around.
Don’t forget artifacts – Add Equip Crit Rate, ATK boost, or stagger multipliers onto your gear to increase your DPS.
Conclusion
Act 3 nightmare bosses penalize poor composition. If single-target DPS is not your concern, you’re going to be in for a world of hurt. Psylocke–Cyclops–Phoenix teams offer balanced DPS and sustain. Ms. Marvel–Wasp–Wolverine, on the other hand, melt bosses using aggression alone. And then there’s the Wolverine–Black Panther/Hulk–Storm composition that’s equally balanced between control and strength.
Regardless of the path they choose, control of energy management, stagger timing, and hero synergy is what makes clean clears and not soul-crushing failures.