Alchemical hydra
| Details | |
|---|---|
| NPC type | Slayer boss |
| Location | Karuulm Slayer Dungeon |
| Combat | |
| Hitpoints | 1100 |
| Attack styles | Ranged Magic |
| Maximum hit | 52 (grey or fully empowered) |
| Attack interval (ticks) | 6 |
| Immunities | Poison Venom |
| Access and rewards | |
| Loot | Hydra's claw; hydra leather; brimstone ring pieces |
| Pet | Ikkle hydra |
The Alchemical hydra is a Slayer boss that requires 95 Slayer to attack. It has four forms, uses ranged and Magic attacks, and drops hydra's claw, hydra leather and the pieces of the brimstone ring.
Getting there
Equip boots of stone, boots of brimstone or granite boots to protect against the dungeon floor. Keep them equipped throughout the trip.
Choose Alchemical hydra in Sarim Hub. Head north and climb the wall, then open the Alchemical door. Confirm the entry and instance dialogues. This entrance creates your own instance without charging an instance token.
Bring a ranged setup, ammunition or weapon charges, food, prayer potions or super restores, and a teleport for resupplying. Ranged is a straightforward choice because the Hydra's ranged defence is lower than its melee and Magic defences. Turn on run and keep enough energy for its special attacks.
Fight
- Watch the first normal attack. The Hydra can begin with either Magic or ranged. Use Protect from Magic or Protect from Missiles to match it.
- Switch between those prayers after every three normal attack animations. Count animations, not individual projectiles. Keep your count through the blue and red form changes.
- Lure each coloured form over the correct vent. Wait for the message that its defences have been neutralised before settling into your attack position.
- Move away from poison pools, keep moving during lightning, and stay inside the clear area during fire.
- When the grey form appears, switch to the opposite protection prayer. From then on, switch after every normal attack and keep avoiding poison pools.
- Collect your loot before leaving. Your instance is destroyed when you leave it.
Forms and vents
The first three forms absorb most of your damage until the correct vent weakens them. Stand beyond the vent so the Hydra follows onto it, rather than standing on the vent yourself.
| Hydra form | Form begins | Correct vent | Special attack |
|---|---|---|---|
| Green | Start of fight | Red, southeast | Poison pools |
| Blue | 825 hitpoints | Green, northeast | Lightning |
| Red | 550 hitpoints | Blue, northwest | Fire |
| Grey | 275 hitpoints | None needed | Poison pools |
Look for The chemicals neutralise the Alchemical Hydra's defences! to confirm that the vent worked. Each blue or red form needs to be weakened again. The grey form does not need a vent.
Keep the Hydra away from the wrong vents. They empower it and make its normal attacks stronger. Standing directly on a vent also burns you.
Protection prayers
Use Protect from Magic for Magic attacks and Protect from Missiles for ranged attacks. Have the right prayer active before the Hydra attacks.
In the first three forms, it changes style after three normal attacks. Some attacks fire two projectiles, but still count as one attack. Poison, lightning and fire specials do not count toward your three-attack total.
The grey form changes style when it appears, then after every normal attack. Switch your prayer after each attack animation so you are ready for the next one. Its normal hits can reach 52, so eat and restore Prayer before you become low on supplies.
Protection prayers help with the normal attacks. They do not protect you from standing in pools, lightning or fire.
Poison pools
The green and grey forms throw poison onto your tile and sometimes nearby tiles. Move at least two tiles away from each marked pool before the splash lands. Do not return to a pool while it remains active.
Lightning
The blue form sends out lightning that moves toward you. Keep moving around the room so it cannot reach your tile. Getting hit damages you and briefly roots you in place.
Continue your prayer count while dodging. The lightning special itself does not count as a normal attack.
Fire
The red form returns to the centre and briefly stuns you. It covers the areas beside you with fire, then sends tracking fire into the clear area where you are standing.
Wait for the initial stun to end, then move away from the tracking fire within the clear area. Keep moving and avoid its trail. Do not cross the walls of fire or run back over burning tiles. Continue your prayer switches once normal attacks resume.
Drops
These notable drop rates are per kill in the normal world, without reward bonuses or extra rolls.
| Item | Quantity | Rarity |
|---|---|---|
| Hydra's claw | 1 | 1/550 |
| Hydra leather | 1 | 1/367 |
| Hydra tail | 1 | 1/367 |
| Brimstone ring piece | 1 | 1/122 |
| Clue scroll (elite) | 1 | 1/114 |
Combine a hydra's claw with a Zamorakian hasta to make a Dragon hunter lance.
Brimstone ring
Ring pieces drop in the order hydra's eye, hydra's fang, hydra's heart, then repeat. The rate above is for receiving any one of those pieces.
Once you have all three in your inventory, use any two pieces on each other and confirm the combination. This consumes the three pieces and gives you a brimstone ring.
Pet
The Ikkle hydra has a 1/1001 chance per pet roll before boosts.