Boss Fight Mechanics — Ancients Wiki

Every boss plays by the same shared rules, no matter which one you've summoned. This page covers the arena, leaving, regen, damage and the protections that stop you from cheesing a fight. It applies to Lamia, Echidna, Thanatos and Hephaestus, and to their Uber versions on top of whatever that page adds. What each boss actually does is best discovered with a weapon in hand.

Solo arenas

Boss fights are solo. When you press Summon at the altar you go straight into your own private arena, and the boss spawns a few seconds later. Nobody else can enter, deal damage or take a share of the loot. Several players can fight the same boss at once, each in their own arena, whenever arenas are free. See Summoning a Boss.

Health and damage

No hidden damage reduction. A boss's health is its real health against every hit, and the boss bar shows all of it. Lamia has 4,000, Echidna 9,000, Thanatos 16,000 and Hephaestus 25,000. Every uber has 100,000.
Boss attacks hit for their full listed damage, and the four normal bosses pierce 20% of your armour.
Big moves are guarded, not immune. During a boss's big moves it takes 90% less damage instead of none. The bar shows GUARDED while it lasts.
Swords and axes deal 3x damage to bosses, including their procs.
Stunned bosses don't take bonus damage.

Dying, leaving and time limits

Death never costs you anything. Go down in a boss arena and you keep your full inventory and XP, then respawn at that boss's altar. You can't rejoin that fight.
Leaving is instant. /boss leave, /spawn, /warp, /hub and the warp menu all take you out of the arena at once, with no re-entry.
Falling off doesn't kill you. Drop off the arena and you are pulled back to the middle of the fight instead of the void.
Fights don't last forever. A drawn-out fight ends automatically after 20 minutes.
Server restarts are safe. If the server restarts during your fight, you get your boss key back.

Combat regen: keep the pressure on

Bosses heal when you stop hitting them. If a boss goes 10 seconds without taking damage, it regenerates 1% of its max health every second until you hit it again. Keep dealing damage and the regen never starts.

No slows, no stun-locks

Bosses are immune to Slowness. Frostblade, the wand beam's chill and thrown potions all slide off.
Bosses can't be stun-locked. Spamming a fast bow or wand doesn't flinch-pause any boss.

Weapons and tools

Ancient wands and bows damage every boss at their full rapid-fire rate. There's no PvE penalty for going ranged.
The Grappling Trinket (Echidna's Strand) works in boss arenas during your own fight.
Auto Clicker (/autoclicker, short /ac) swings your sword or axe as fast as the weapon charges and hits whatever mob or boss is under your crosshair. It doesn't pick targets for you and never hits players or mine guards. It is a perk of the top rank (Everflame) and the paid season pass, and the free pass gives trial time. It replaced /ma.

Boss Mastery

Season kills of a normal boss raise your damage against it (up to 10% increased) and lower the damage it deals to you (up to 5% reduced). See Bosses Overview for the milestones.

When you're ready to chase rewards, head to Boss Loot & Drop Announcements.

Version history

v4.0.4

Fixed false auto-clicker warnings and kicks while using /ac.

v4.0.0 (Map 4)

Boss fights are solo: only the summoner can enter, deal damage and get loot. Parties are gone.
Bosses no longer have hidden damage reduction, attacks hit for their full listed damage, and the health bar shows full health. The four normal bosses pierce 20% of your armour.
Bosses no longer go fully immune during their big moves. They take 90% less damage instead.
Swords and axes deal 3x damage to bosses, including their procs. Stunned bosses no longer take bonus damage.
/spawn, /warp, /hub, the warp menu and /boss leave take you out of an arena at once. Falling off an arena pulls you back to the middle of the fight.
If the server restarts during a boss fight, you get your boss key back.
The Grappling Trinket works in boss arenas during your fight.
/ma is now /autoclicker (/ac). It swings at whatever mob or boss is under your crosshair instead of picking targets.
Added Boss Mastery.

v3.0.0

Dying to a boss now respawns you at that boss's altar instead of at spawn.
Boss abilities no longer lose most of their damage to armor.
Fixed bow arrows bouncing off bosses and hanging in the air around them instead of flying on.
The shared rules now also cover the four Uber bosses.

v2.0.0

Bosses now slowly regenerate when left alone. 10 seconds without taking damage heals 1% of max HP per second.
Bosses can no longer be slowed. All Slowness sources are ignored.
Bosses can no longer be stun-locked by rapid fire. Thanatos and Hephaestus stop flinch-pausing and now chase continuously like the other two.
Ancient wands and bows now damage every boss at their full rapid-fire rate.