OSRS Nylo Boss Guide: Nylocas Vasilias, Waves and Roles

Nylocas Vasilias at a Glance

Nylocas Vasilias is the boss of the third Theatre of Blood room, and most players just call the room Nylo. It is two fights in one. First your team holds four pillars against 31 waves of nylocas, each of which can only be hurt by one combat style. Then Vasilias drops into the middle of the room: a level-800 boss with 2,500 hitpoints in a five-player Normal Mode raid.

Vasilias changes form every 10 ticks (6 seconds) and never picks the same style twice in a row. The colour of its carapace tells you the style it is using and the only style that can damage it: white is melee, green is ranged, blue is magic. Hit it with the wrong one and your damage comes back at you while it heals by the same amount.

Requirements and Getting There

Nylo has no requirement of its own. You reach it by clearing the Maiden of Sugadinti and the Pestilent Bloat, and the Theatre itself only needs Priest in Peril for access to Morytania. The first supply chest opens when Bloat dies, so restock there and grab a stamina potion: the waves involve a lot of running, most of all for the meleers.

The boss requirements checklist lists the other raid and boss gates if you are planning several at once.

The Nylocas Waves: Pillars, Colours and Roles

The waves come before the boss. 31 of them walk out of the tunnels, mixing three breeds: grey Ischyros (melee only), green Toxobolos (ranged only) and blue Hagios (magic only). Attack one with the wrong style and you can no longer damage that nylo at all, so one misclick hands the kill back to a teammate.

Most nylos walk to one of the four pillars and attack it. A broken pillar collapses for up to 50 damage on the whole team, and if all four break the team dies on the spot. A few nylos go for players instead; kill these aggressive ones first. Any nylo still alive 30 seconds after spawning self-destructs for up to 18 (small) or 21 (large), which mostly catches meleers standing by the pillars.

The waves are not random, so learning one role's waves is how people get consistent. From wave 16 some nylos flicker between styles in a fixed pattern. Waves 1 to 19 pause once 12 nylos are alive, and from wave 20 the cap rises to 24. More nylos alive at once means faster pillar damage, so slow kills snowball.

Nylos have no defence to speak of, so strength bonus beats accuracy. Meleers bring dual macuahuitl, or glacial temotli or sulphur blades if they don't have them, because a scythe wastes hits on 1x1 nylos unless several line up. Rangers use the toxic blowpipe and bring chinchompas for clumps. Mages use the Eye of Ayak or a 4-tick staff and save barrage for when the room gets hectic. The ranger usually shares a stamina potion with a Lunar potion-share spell before wave 1.

Recommended Gear for the Boss

For the boss, carry one weapon per form. White: the scythe of vitur, Soulreaper axe, blade of saeldor, noxious halberd or abyssal tentacle, and Osmumten's fang. Green: the twisted bow or toxic blowpipe. Blue: the sanguinesti staff or Eye of Ayak, then the trident of the swamp.

Inventory and Supplies

• Your wave weapon plus a weapon for each of the boss's three forms.
• Prayer potions or super restores. During the boss you change protection prayer every 6 seconds.
• Brews or food. Through the right prayer its ranged and magic hits top out at 17 and its melee is fully blocked; off prayer it hits up to 70.
• A stamina potion, sipped or shared before the first wave.

Mechanics: Attack Styles, Max Hits and Immunities

Hard Mode changes

Max hit rises to 105. On green, its ranged attack hits everyone within 2 tiles of its target, so spread out with a 3-tile gap. On blue, its magic attack bounces from the target to every other player for the same damage, ignoring Protect from Magic. Players within 2 tiles of the target take half, and if the whole team stands on one tile only the target is hit.

Entry Mode changes

Vasilias changes colour more slowly. In a solo party every nylo can scale down to 20% of its hitpoints, but the number you have to kill stays the same, so the waves still overwhelm unprepared solo players. The room still fails if all 4 pillars fall.

Where Nylocas Vasilias Sits in the Theatre

Nylo is room three of six. Before it come the Maiden of Sugadinti and the Pestilent Bloat; after it come Sotetseg, Xarpus and Verzik Vitur. The next supply chest only opens after Sotetseg. When Vasilias dies, every player's hitpoints, prayer, run energy and special attack energy refill, though drained stats stay drained.

Fight Strategy: Waves, Then the Boss

1. 1

   Before wave 1, sip or share a stamina potion, repot, and agree who takes which colour.

2. 2

   During the waves, kill aggressive nylos first, then the newest spawns, smallest first.

   Never stand idle: if none of your colour is in the room, switch and help until they come back.

3. 3

   When Vasilias drops, heal and boost in the short pause.

   It always spawns in its white melee form, so turn on Protect from Melee before the first attack.

4. 4

   Open with specials:

   one Bandos godsword for Defence, everyone else on dragon claws or crystal halberd.

5. 5

   Every 6 seconds it changes colour.

   Swap prayer and weapon to match. Your attack stops when it changes, and one form lasts two attacks with a 4- or 5-tick weapon, three with a 3-tick weapon or four with a 2-tick weapon.

6. 6

   Never attack the wrong colour.

   The full hit comes back to you and the boss heals.

Drops and What Nylocas Vasilias Is Worth

Vasilias drops one item of its own, the lore book Arachnids of Vampyrium, and stops dropping it once you have read it. Uniques only come from the chest after Verzik, three rooms later; the Theatre of Blood guide lists them and what Entry Mode can't roll.

Combat Achievements

Perfect Nylocas is the Master-tier task for this room: kill Vasilias without anyone in the team attacking a nylo with the wrong style, without a pillar collapsing, and without anyone taking a Vasilias hit off prayer. Don't barrage or use chinchompas on that attempt. Kill nylos fast enough that pillar health never matters, and highlight a nylo before attacking it so a flicker does not catch you out.

Task lists change with updates, so check the current list in game. The Combat Achievements guide covers how the tiers fit together.

Ironman Notes

Ironmen get full Theatre rewards when they raid with other players, and the chest's uniques exist nowhere else in the game. A Hardcore Ironman loses the status on any death in the Theatre, Entry Mode included. Entry Mode is still the cheap place to learn the waves, because a wipe there sends the team back outside the room with unlimited attempts instead of ending the raid.

Common Mistakes and Death Causes

• Hitting a wave nylo with the wrong style. You can no longer damage it, and it keeps chewing the pillar.
• Chasing pillar nylos while aggressive ones are still hitting the team.
• Standing next to a pillar when an old nylo self-destructs for up to 21.
• Letting nylos pile up. Up to 12 can be alive in waves 1 to 19 and 24 after wave 20, and every extra one speeds up pillar damage.
• Forgetting to swap prayer when Vasilias changes colour. Off prayer it hits up to 70.
• Clicking the boss again after a colour change before swapping weapons.

FAQ

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