* Mutators are modifiers to enemies that spawn from that particular lane in the Onslaught game mode. These can be an advantage or disadvantage to the enemies or can grant additional effects. Double Mutators start at floor 22.* As of the Shifting Sands Update Pain Aura has been removed due to poor performance. To compensate, Bloodlust, Trollblood, Speed Demons, Berserked, and Reckless has been added to the game.
{| class="wikitable"
|-
! Name !! Icon !! Description !! First Floor Found on || CounterNotes
|-
| Headstrong || [[File:Headstrong.png|50px]] || Enemies cannot be stunned. || Floor 3 || Don't use stunning defenses on these lanes.
|-
| Pile it on || [[File:Pileiton.png|50px]] || Enemies take increased damage per condition they are under . || Floor 3 || Use many different +25% additive extra damage if conditions from defenses and abilitiesare met. Conditions are the same things for Controlled Burn.
|-
| Power Block || [[File:Powerblock.png|50px]] || All enemies are immune to damage from Abilities, but take increased weapon damage . || Floor 3 || Don't use abilities. Hero Attacks deal double damage.
|-
| Unstoppable || [[File:Unstoppable.png|50px]] || Enemies are immune to slow effects . || Floor 3 || Don't use slowing defenses on these lanes.
|-
| Abominable || [[File:Abominable.png|50px]] || Enemies inflict slow with their attacks . || Floor 3 || Avoid letting enemies hit defenses; slow or stun themEnemy attacks reduce defense rate by ~30%.
|-
| Soft Spot || [[File:Softspot.png|50px]] || Enemies have increased resistance, but take extra weakpoint damage . || Floor 3|| Deals extra damage to weakpoints, otherwise 20% less damage (defenses can't hit weakpoints).
|-
| Armored || [[File:Armored.png|50px]] || Enemies take reduced Physical damage, and increased Magical damage . || Floor 3 || Use magic magical defenses (indicated by purple , +25% from magical damage, -50% if you use physical damage numbers).
|-
| Toxi-kaze || [[File:Toxikazi.png|50px]] || When Kobolds die, they will leave an area that deals damage to players inside . || Floor 6 || Rely on defenses to handle the laneKolbold's death drops mushrooms that deals 2% hero's maximum health per second and each stack.
|-
| Lethargic || [[File:Lethargic.png|50px]] || Enemies start stronger, but get weaker the longer they live. || Floor 9 || Keep your defenses towards the end Enemies deal 125% extra damage, over time they'll deal 75% of the lanetheir original damage.
|-
| Brittle || [[File:Brittle.png|50px]] || Enemies start with higher health, but receive a damage resistance debuff every time they are hit with hero abilities . || Floor 9 || Enemies gain 50% extra health. Use your cheap hero unique abilities to weaken enemiesdebuff them by 10%, has Additive stacking.
|-
| Wall Leech || [[File:Wall leech.png|50px]] || Enemies heal when damaging towers . || Floor 10 || Slow and stun enemies so they don't reach your blockades.
|-
| Maximum Effort || [[File:Maximum Effort.png|50px]] || Enemies have more health, but get weaker with each unique source of damage that hits them . || Floor 10 || Stack many Enemies gain +50% health and take 10% increased damage per unique source with additive stacking. Each source can be added through different defenses, elemental combos, attacks, pet and hero abilities.
|-
| Phased || [[File:Phased.png|50px]] || Enemies move slower, but they can phase through blockades . || Floor 10 || Slow Enemies move at around 60-70% of their original speed and stun enemies to make up for a lack of viable no longer target blockades.
|-
| Proximity || [[File:Proximity.png|50px]] || The closer a source of damage is to an enemy the more damage it deals . || Floor 10 || Use traps +50% damage at 0 range and auras for close -50% damageat 5,000+ range.
|-
| Long Shot || [[File:Long Shot.png|50px]] || The farther a source of damage is to an enemy the more damage it deals . || Floor 10 || Use projectile defenses from far away+50% damage at 5,000+ range and -50% damage at 0 range.
|-
| Enraged || [[File:Enraged.png|50px]] || Enemies start weaker, but get stronger the longer they live . || Floor 10 || Place defenses Enemies start at the beginning 75% of lanes their original attack damage and eventually rises to kill quickly125% over time.
|-
| Cursi-Kaze || [[File:Cursi-Kaze.png|50px]] || When Kobolds die, they will leave an area that debuff towers and defenses . || Floor 13 || Slow Kobold's deaths Reduces the range, damage and stun kobolds so they don't make it to your last line attack rate of the affected defensesby 25% per stack, stacks are multiplicative.
|-
| Controlled Burn || [[File:Controlled Burn.png|50px]] || Enemies can only be damaged while drenched, oiled, frozen, poisoned, chilled or stunned . || Floor 20 || Use defenses or abilities to apply one or more of the listed conditions.
|-
| Detonator || [[File:Detonator.png|50px]] || Enemies explode when killed . || Floor 20 || Keep defenses out Explosions has knockback and deals 5% of explosion-range and keep an eye on blockade the target's maximum health.
|-
| Bullet Sponge || [[File:Bullet Sponge.png|50px]] || Enemies have a small anti projectile shield . || Floor 20 || Use traps, auras, and anything else that doesn't shoot projectilesThe shield will be removed after dealing 10% of enemy health as damage. The enemey will take damage as normal as soon as the shield is removed.
|-
| Pain Aura (Removed) || [[File:Pain Aura.png|50px]] || Enemies deal damage around them . || Floor 20 || Keep defenses out Enemies Deal 5% of lanes so they donthe target't take s maximum health as damagearound them. Once per second.
|-
| Spellbreaker || [[File:Spell Breaker.png|50px]] || Enemies take reduced Magical damage, and increased Physical damage . || Floor 20 || Use +25% damage from physical defenses (indicated by white damage numbers)and -50% damage from magical damage.
|-
| Vampiric || [[File:Vampiric.png|50px]] || Enemies heal when dealing damage . || Floor 20 || Rely Enemies heal for 5% of their maximum health on hit.|-| Bloodlust || [[File:Bloodlust.png|50px]] || Enemies on receiving damage now move at +30% speed for 5 seconds. || ? || |-| Trollblood || [[File:Trollblood.png|50px]] || Enemies now heal for +2% of their max hp every second. || ? || |- | Speed Demons || [[File:Speed Demons.png|50px]] || Enemies are faster, but slow effects last longer on defenses to them. || ? || Enemies move 50% faster.|-| Berserked || [[File:Berserked.png|50px]] || Enemies now take out enemies; keep them away from blockades+50% more Damage and deal +50% more Damage. || ? || |-| Reckless || [[File:Reckless.png|50px]] || Enemies now have +50% Movement Speed and +50% Damage taken.|| ? ||
|}