Alchemical Hydra

The Alchemical Hydra is a multi-phase boss with unique fountain mechanics that affect damage output. Learning the attack patterns is essential for efficient kills.

Stats

Stat	Value
Combat Level	426
Hitpoints	1,100
Defence	300
Weakness	Stab & Ranged
Poisonable	Yes
Slayer Task	Yes

Requirements:

• 95 Slayer
• Boots of Stone (or variant)

Phase Health Thresholds

Phase	HP Range	Color
Phase 1	1100 - 825	Green
Phase 2	825 - 550	Blue
Phase 3	550 - 275	Red
Phase 4	275 - 0	Black

Fountain Mechanic

Important

Hydra has ~50% damage mitigation unless you lure it to the correct fountain for each phase!

Phase	Fountain Location	Color
Phase 1	South-East	Red
Phase 2	North-East	Green
Phase 3	North-West	Blue
Phase 4	N/A (permanent 50% reduction)	-

Base Attack Pattern

Hydra follows a 3-attack rotation:

1. Starts with ranged attack
2. Three attacks of one style
3. Throws poison on floor
4. Switches to magic (three attacks)
5. Repeat

Phase-Specific Mechanics

Phase 1 (Green)

• Only base mechanics apply
• Lure Hydra to the red fountain (SE)

Phase 2 (Blue)

• Lightning: Blue lightning appears and tracks the player
• Lightning doesn't disappear until Phase 3
• Getting hit stuns you for 2.4 seconds (4 ticks)
• Lure Hydra to the green fountain (NE)

Phase 3 (Red)

• Fire Wall: A wall of fire moves toward the middle, trying to trap you
• Once placed, the wall stays until phase ends
• Standing in fire burns you for ~10 seconds
• Move to another tile to escape the burn
• Lure Hydra to the blue fountain (NW)

Phase 4 (Black)

• Fountains no longer work - 50% damage reduction is permanent
• Attack pattern changes to 1:1 (alternating ranged/magic)
• Poison thrown after first 7 attacks, then every 14 attacks

Tips

Phase Transition Note

If Hydra has done 2 ranged attacks and gets phased, it resets the count to 0. For example, if phasing from Phase 1 to Phase 2 after 2 ranged attacks, Hydra will do 3 more ranged attacks in Phase 2 before switching to magic.

Location

Boss Teleports > Alchemical Hydra