Alchemical Hydra/Strategies
The Alchemical Hydra is a level 95 Slayer boss encountered in the Karuulm Slayer Dungeon. In order to fight it, players must be assigned a Hydra task.
To reach the boss, players must run north past the Tasakaal, then east past the Hydras. They will then reach the entrance to the lair by Orrvor quo Maten. Alternatively, players with level 88 Agility can reach it safely by using the mysterious pipe just behind Kaal-Ket-Jor, though this takes roughly the same time as reaching it by running past the Hydras.
Fight overview[edit | edit source]
The fight is instanced; if players die while fighting the Hydra, then they may reclaim their items from Orrvor quo Maten outside for 100,000 coins each time. Dying elsewhere with items still held by him will result in them being lost forever.
Note: While the Hydra is in the room, players cannot leave through the doors, as they are jammed when this occurs. Teleports will still work, however. The Hydra has a respawn time of 20 seconds.
The Hydra has four phases, each one beginning upon hitting or going past each 25% health threshold (~275 health). A head will fall off each time this occurs as the Hydra roars and changes forms, signifying the start of the next phase.
The Hydra attacks with both Magic and Ranged, with the left heads attacking with magic and the right with ranged. In the first two phases, this consists of two instant hits that deal less damage individually. In the last two phases, this will consist of one hit that does higher individual damage. The Hydra will begin the fight with either combat style. For the first three phases, after every three basic auto-attacks, regardless of damage dealt, the Hydra will sway its heads backwards as a warning indicator that it is changing combat styles. Phase-specific special attacks do not count toward these three attacks. Players should be aware that the Hydra's phase transition animation can override the attack swapping animation, so counting the attacks is still beneficial.
During the first three phases, the Hydra's carapace is strengthened and will immensely reduce incoming damage by 75% of what it would have dealt. This must be removed by luring it to the appropriate chemical vent. The Hydra will Roaaaaaaaaaaar! via a message above its heads when it gets sprayed by the correct vent. If it gets sprayed by chemicals from an incorrect vent, its enrage stack will go up, increasing the damage of its attacks. At the start of each phase, the Hydra will perform three auto-attacks before performing a special attack.
Poison[edit | edit source]
In this phase, the Hydra starts with a green carapace, and should be lured to the red chemical pool. After the first kill, the player should stand right next to the red chemical vat (to the west) so that the Hydra is automatically lured to the red chemical pool as soon as it spawns.
After the first three attacks, the Hydra will launch 4 or 5 poison blobs around the player's location; 1 on the player and 4 randomly around it. The blobs have a 3x3 splatter effect dealing up to 7 damage, and standing on the poison pools will deal up to 12 poison damage per tick. Both will cause a poison effect that deals 4 or 6 damage; if players get poisoned, immediately clear its effects. The best way to avoid this attack is by standing west of the red chemical vat, all the way south, then move north two tiles when the Hydra is positioned over the chemical pool. When it spits poison, move west two tiles - this avoids the one targeting the player, and the other four will splatter east.
Once the Hydra reaches 75% of its health, the bottom-right head falls off and it changes its carapace to blue. Next, the player should run north to the green vent.
Lightning[edit | edit source]
Now with a blue carapace, the Hydra should be lured to the green chemical pool.
Throughout the phase, the Hydra will launch an electric ball in the centre of the room, which spawns four lightning currents in the four corners of the chamber, although the order in which they appear in is random. The four pieces of lightning converge on the player's location. Getting hit by them will bind the player and deal up to 20 damage.
Starting near the middle of the room and looping around one of the last lightning spawns, to escape the box they form, is the easiest way to avoid their damage. Players may also hug the northern wall and quickly move their way west while damaging the Hydra, which works especially well with any ranged weapon with a distance of 10. It is also possible to trap the lightning by standing in the north-west corner, moving one tile diagonally south-east when the lightning is two tiles away from you, and instantly moving one tile north. This does not despawn the lightning, so if the player were to move off of the tile, the lightning will start following them again.
Once the Hydra reaches 50% of its health, the bottom-left head falls off and it changes its carapace to red. Next, the player should run west to the blue vent if not already there from the lightning.
Note: If the Hydra transitions to the next phase while there is lightning on the field, they will dissipate immediately.
Flame[edit | edit source]
Now with a red carapace, the Hydra should be lured to the blue chemical pool.
Throughout the phase, the Hydra will occasionally walk to the centre of the chamber and face the direction the player is at. Once it reaches the centre, it will inflict a stun on the player, but they can still attack it. If the player is underneath the Hydra, then it forces them out into a random direction. Upon reaching the centre, it breathes 5x5 layer of fire to the player's sides based on their location before staring down the middle and launching a tracking fire. This tracking fire follows the player's movement, and travels significantly faster the further the player is (or if they start running). Turning off run and walking in a line as the fire trails is the best course of action. Getting hit by any of the fires will result in the player taking up to 20 damage, followed by a subsequent bleed of 5 damage for five hits. Moving onto another fire resets the bleed. Fires may be tile skipped, though it's only recommended to do so after the tracking fire stops. The Hydra does not attack until four seconds after the tracking fire is sent out.
Similarly to the lightning trap in the previous phase, the flames can be trapped in by standing right next to the Hydra while facing a corner so it uses the corner variant; as soon as the fire is launched from the Hydra's mouth, immediately corner run to the other tile. The flame, which would try to track the player, instead ends up trapped on the first flame tile, preventing it from extending.
Once the Hydra reaches 25% of its health, the middle head falls off and it changes its carapace to grey.
Note: If the Hydra transitions to the next phase while performing this attack, it ends abruptly. This also includes the tracking fire, but any fires started before the phase transition will still persist as usual. For the duration of the side fires, the Hydra also becomes a solid NPC, meaning that it is not possible to walk under it.
Enraged[edit | edit source]
Now with a grey carapace, the Hydra no longer needs to be lured to any chemical pools for this phase, as its damage reduction ability does not reset. During this phase, the Hydra's attack speed will increase to every four ticks, and its enrage stack will increase to max, allowing it to deal up to 55 damage per hit.
The Hydra starts off this phase with the combat style opposite of what it used in the previous phase; if it attacked with magic, then it will start the phase with ranged. If the Hydra attacked with magic and changes to ranged as it transitions phases, it will still start with ranged attacks. Like Zulrah's unusual green form near the end of its phases, the Hydra will alternate between both combat styles after every single auto-attack; there is no warning animation for this, unlike the previous three phases. Continue to switch prayers with each basic attack for the remainder of the fight. The player can safely switch to the next prayer as soon as the Hydra starts its attack animation for the current attack.
After the first three auto-attacks, the Hydra will use the poison attack from phase 1, and will continue to use it after every nine subsequent auto-attacks. Be aware that the poison special attack does not count as a basic auto-attack; the Hydra's next attack style will still be the opposite of the auto-attack it used before the poison special. If the Hydra is killed just as it sends an auto-attack, it will deal no damage. Poison blobs will still deal damage, however.
Players may choose to bring a bracelet of slaughter to extend their slayer tasks, and sometimes bring it as a switch so that gloves with offensive stats can be worn for the majority of the kill. If going with this option, remember to switch to the bracelet sometime during this final phase. It can be convenient to switch to the bracelet while dodging the poison special, as prayer does not have to be changed during this attack, though optimally the offensive gloves should be worn as long as possible.
Equipment[edit | edit source]
Prayer bonus is prioritised over ranged accuracy because of the boss's relatively low defensive stats. Alternatively, players may use gear that maximizes ranged accuracy if they are confident with prayer flicking, as it greatly reduces the need for prayer potions. With sufficient experience, barely any damage should be taken most kills; the only unavoidable damage players may take is the first hit at the start of kill, and self-inflicted damage from Divine potions or the special attack of Ruby bolts (e).
Inventory[edit | edit source]
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- About 4–20 prayer potions or super restores. Each kill should take around 2:00-2:30 with a toxic blowpipe, so generally 2-3 doses are required per kill (slightly less for twisted bow users).
- Some food; 4-10 sharks or manta rays. As the player becomes more proficient at fighting this boss, they should take very little damage per kill, so excess food can be replaced with more prayer potions.
- Antidote++
- Divine ranging potion, ranging potion, or bastion potion (the latter is largely superfluous, as all damage taken in the fight can be mitigated with prayer and good positioning once the player is experienced enough)
- House tablets or rings of dueling to restore stats and bank
- Rada's blessing 4 for fast teleport back, if using a twisted bow (can be equipped if using bow of Faerdhinen or toxic blowpipe)
- Zaryte crossbow with Ruby dragon bolts (e) for its special attack to start off fights. Particularly powerful when combined with the Lightbearer.
- Toxic blowpipe for healing special attack if using twisted bow or bow of Faerdhinen, or for using after the Alchemical Hydra has been brought below 420 Hitpoints if using a crossbow with blowpipe and dragon darts, or below 240 Hitpoints if using amethyst darts.
- Divine rune pouch with runes for High Level Alchemy and Teleport to house (or two open slots for rune drops if using tabs/ring of dueling)
- (Optional) Bracelet of slaughter to extend the task
- (Optional) At 74 herblore crystal dust can be brought to make the Ranging potion drops into divine Ranging potions
- (Optional) Bonecrusher or bonecrusher necklace to auto-bury hydra bones. Bonecrusher necklace can also be equipped during boss death animation to restore an extra 8 prayer points per kill.
- Strength bonus is preferred over prayer bonus for melee
- Inquisitor's armour provides an extra +2 prayer bonus over bandos making it slightly better if you are flicking correctly. Bandos has more defence to tank range hits without prayer.
- Range is recommended over melee, but it can be viable if you have low range or want to cut out the ammo and scale costs
- Melee with dragonhunter lance is similar dps to killing with blowpipe if you have a good strength bonus
- Learning to skip the flame phase will speed up kills a lot
Inventory[edit | edit source]
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- 1-2 Super combat potions or Divine super combat potions
- 1 Antidote++
- 4-15 Prayer potions, find what works for you
- Fill your inventory with the rest high healing food like, sharks or manta rays
- Don't forget your special attack weapon
- Divine rune pouch with runes for High Level Alchemy and Teleport to house (or two open slots for rune drops)
- House tablets or rings of dueling to restore stats and bank if not using divine pouch
- (Optional) Bracelet of Slaughter to extend the task
- (Optional) Bonecrusher or Bonecrusher necklace to auto-bury hydra bones. Bonecrusher necklace can also be equipped during boss death animation to restore an extra 8 prayer points per kill.