NEW ROCKBLOCK GUIDE FOR DOOM DELVE (OSRS)


Date	2025-07-31
Type	guide
Video	youtu.be/draz0HZBq00

Summary

Gnomonkey presents the final version of his rock block (car park) tech for the Doom of Mokhaiotl after the car park exploit was patched. It adds an outside rail rock so the boss is dragged across two shockwaves and then the room centre, which gets more Twisted bow shots in and works on all waves. He also covers rubble dodging, the Chally punish, double Zaryte crossbow, stalling for a bonus hit splat, and the holy water mechanic once it is fixed.

Outline

0:00 The car park tech was patched: shockwaves now destroy the rock under the boss
0:32 New rock block: an extra outside rock on a rail tile blocks the first shockwave
1:59 Green tiles that let you Chally punish from the corner of the boss
2:25 Avoiding rubble so your rock lands where you want
4:01 Setting up on waves 6-7: stalling below 75% and why west/south drags fail
5:29 Executing the strategy: drag the boss onto the rock, then bait it to the middle
9:04 Alternative ranged strategy: blowpipe with a Scorching bow
9:57 Recovering from a misplaced rock
10:56 Optimal Zaryte crossbow usage right before the shield phase
13:56 Perfect rock dodging by clicking onto a shadow tile
15:26 Chally punish technique and why it is worth the spec
18:19 Rubble dodging detail and future-proofing for holy water and orb clearing
20:28 Maximising phase damage: stalling for double Death Charge and the bonus hit splat

Topics covered

Doom of Mokhaiotl: rock block method

(0:00) After a patch to the Doom of Mokhaiotl, the car park tech still lets you park the boss on a rock, but the shockwave now destroys the rock under the middle of the boss, so you can no longer sit there for the whole car phase.
(0:32) Gnomonkey's modified tech adds a second, outside rock to car park via two 'rails' of tiles on the sides: you place one rock on the car park tile and one on a rail tile; the first rock under the boss blocks the first shockwave and the second rock lets you hide for the next.
(0:59) After the shield phase you lure the Doom of Mokhaiotl onto the car park rock, which blocks the first shockwave, stand next to the wall to keep the boss in place and hide behind the second rock, then drag the boss to the centre of the room and hide behind one more rock.
(1:31) Gnomonkey considers the new rock block better than car park because the longer the boss is dragged around, the more Twisted bow shots you get; it gives about two extra Twisted bow shots in total, greatly increasing the odds of killing the boss before the orb phase.
(1:59) All the tiles work as long as you place a second rock for car park, but if you place the rock on a green tile it drags the boss so you end at its corner, out of range, so you can Chally punish; starting a Chally punish from a white tile drags you into melee range of the boss, likely in acid.
(2:25) On cave 8 the Doom of Mokhaiotl throws two rocks that both land under where you are standing; you wait for the first rock to explode and place the rocks where you stand.
(2:25) Gnomonkey says that if you are hit by any rubble on the second rock, the rock is placed on a random tile instead of where you want it.
(2:56) To avoid rubble when placing the rock, wait for the rock to explode, step out immediately to a tile with no shadow, then step back onto a tile that had a shadow; Gnomonkey says the boss cannot place rubble on a tile you stepped to.
(4:01) Gnomonkey says dragging the Doom of Mokhaiotl south or west always destroys the rock, the same way car park only works on the north and east side, and this also applies to the second drag, which is why he had to build a new method.
(4:01) On waves 6 and 7 there are no double rocks, so you must stall: the shield phase starts at 75% health, so if you do too much damage you will not have time to place the rocks.
(5:29) Gnomonkey places one rock on car park and one on a green tile; it can be any of the green tiles, and the green tiles drag you to the corner of the Doom of Mokhaiotl.
(5:59) After the shield phase, drag the Doom of Mokhaiotl against the wall near the rock; you only need to stand fairly close to the rock, not on an exact tile, and the boss will move on top of it.
(5:59) When the Doom of Mokhaiotl is on top of the rock, its shockwave does nothing; Gnomonkey says players are scared to go under the boss but the shockwave does not hit there, so you can reposition after getting out of the way.
(6:28) To bait the second dash, stand against the wall one or two tiles from the boss (or directly under it if acid is a problem); the boss slowly turns toward you and stays in place, and the pre-placed rock blocks the second shockwave, though Gnomonkey says there is no clear cue and you learn when the boss reads your position.
(6:58) After the second shockwave, run as fast as you can to the middle of the room because the further you get the boss to dash, the more damage you get to do before the phase ends; then hide behind any rock far out of range, often in a corner, and keep shooting as you run.
(8:31) If you place only one rock (because you pushed the boss into the shield phase too early), the rock block still blocks one shockwave, so you can drag the boss to a corner and hide behind another rock.
(9:57) Gnomonkey says that even if you place a rock in a bad spot, you can still usually make it by running to hide behind rocks, as long as the first rock is on the right tile.
(19:56) In the video description, Gnomonkey says you can fit 1 Zaryte crossbow shot and 8 Twisted bow shots during the car phase with this tech, and during the first two shockwaves you are in range for a Blowpipe or Dragon knife specs; he reached wave 24 with it.
(22:50) Gnomonkey says the rock block version in this video works for all waves without stipulations like thralls or zero grubs up, and that jmods confirmed the tech is fine and fair; he says it is very similar to the car park tech that was patched.

Doom of Mokhaiotl

(2:25) At the Doom of Mokhaiotl, when it throws rocks you step to a tile without a shadow after the first rubble lands, then immediately click back onto a tile that had a shadow, which avoids all rubble and the prayers while setting up the rock.
(13:56) Gnomonkey says the Doom of Mokhaiotl will never send the second set of rubble onto a place where rubble has just landed, so clicking onto a tile with a shadow right after the first explosion is guaranteed safe and lets you cue up a click on the boss and keep shooting while flicking prayers.
(18:19) To perfectly dodge the rocks, dodge the first set of shadows and click onto the shadow tile, then start praying; Gnomonkey says this is similar to a boss in another fight but does not elaborate, and that if you do it you will never take damage and can still keep shooting.
(18:51) Gnomonkey says using the rails and dodging the rubble effectively is the biggest thing for pushing very deep delves.

Doom of Mokhaiotl: melee punish

(15:26) Gnomonkey changes his opinion on the Chally for the Doom of Mokhaiotl melee punish: it gives the most damage on the punish but costs 30% spec; he used to say always use a Scythe, but from a green tile the Chally is better.
(15:54) For the Chally punish, get the boss around 84% health (a sweet spot) and do not keep shooting once you have done a big hit near 90%; when the prayer shield goes up, click a green tile and then the boss, and you run straight to the boss's corner where there is the best chance of no acid.
(15:54) If you use a halberd for extra range in longer delves, you must also start the punish from a green tile.
(16:23) A Scythe has better DPS than a Chally spec on paper because it is 5 tick versus 7 tick, but Gnomonkey says lost ticks do not matter on the melee punish because the boss does not attack you and there are no grubs yet.
(16:49) Gnomonkey pushes the Doom of Mokhaiotl into the shield phase with a big Chally punish, gets spec back from Death Charge off the grubs, and then continues; the result leaves the boss at a similar health to a Zaryte crossbow opening but spending 30% spec instead of 72 to 75%.
(16:49) Gnomonkey says that using a Scythe from there would have poisoned him and hurt a lot, and also do less damage than the Chally.

Doom of Mokhaiotl: gear and inventory

(9:04) If you do not have a Twisted bow, such as using a Scorching bow, the Blowpipe is your best option at the Doom of Mokhaiotl because it is about 5% worse than a Twisted bow, and the rock block tech lets you blowpipe almost the whole time.
(9:31) Without a Zaryte crossbow you can use Blowpipe specs, which are 100% accurate in car phase and give health back; after the second shockwave put your Scorching bow back on and run, and keep piping if a rock is close to the boss.
(22:03) Gnomonkey says Dark light is superior to Ember light when stalling the shield phase because it is so weak (about 8 strength bonus) that your damage is irrelevant and you are just damaging the boss with grubs, and it is cheaper in death costs.
(22:30) In the video description Gnomonkey gives a spec order of Zaryte crossbow, Chally punish, Blowpipe spec, and for the car phase Zaryte crossbow, Dragon knife, Blowpipe spec; he says a Dragon knife in the car phase surpasses a Zaryte crossbow when the boss is below 350 HP.
(23:29) In the video description Gnomonkey says he is back to Void because he needs to get better at zero-damage prayer flicking and out-DPSing the car phase for late delves, though Masori is still great.

Doom of Mokhaiotl: car attack

(10:56) Gnomonkey pushes the Doom of Mokhaiotl down toward 75% and uses a Zaryte crossbow spec right before the shield phase, because the damage the Zaryte crossbow does before you send the boss into the shield phase carries into the car phase, giving a very high chance of killing it before the orb phase.
(11:52) Gnomonkey says the Doom of Mokhaiotl is hit around 85% or below after a big Twisted bow hit; the Scorching bow maxes a lot lower so you can get the boss lower, maybe below about 81%, without accidentally sending the shield phase before the rocks are down.
(12:24) When the Zaryte crossbow spec lands right before the shield phase, the Doom of Mokhaiotl stops attacking you because it moves into the shield phase, which protects you and increases your odds of getting through the orb phase.
(14:58) With double Death Charge and a Lightbearer stall in the shield phase you can get a second Zaryte crossbow spec before the car phase, which Gnomonkey says makes the odds of an orb phase sub 5% (his example had the boss at 416 HP going into the car phase).

Doom of Mokhaiotl: shield phase

(20:28) When you have no spec energy left before the Doom of Mokhaiotl car phase, Gnomonkey stalls the shield phase by keeping grubs from reaching the boss, which lets the Lightbearer recharge your spec and gives a second double Death Charge as the timer ticks.
(20:59) There is a hidden mechanic: the longer the Doom of Mokhaiotl shield phase takes, the larger a bonus hit splat you deal after it ends, which Gnomonkey says is capped at 50 damage after a cap was added; the one-shot short worked because it was not yet capped.
(21:32) The bonus hit splat waits for your first attack, so your Zaryte crossbow spec takes effect before it; if you stall until you get your Zaryte crossbow spec back you get roughly a 40 to 50 bonus hit splat.
(21:32) While stalling, Gnomonkey lets melee grubs go into the boss because they are hard to remove with acid around, and tags all others with a Dark light.
(22:30) In his example the Zaryte crossbow after stalling did 38 damage as the bonus hit splat, and a Ruby bolt spec did 91 because it landed right before the bonus hit splat.
(23:00) Gnomonkey says extra shots from the parking lot tech, a stalled extra Zaryte crossbow spec and the bonus hit splat together give the highest odds of skipping the orb phase.

Doom of Mokhaiotl: holy water

(19:23) Gnomonkey says the holy water punish was broken at the time and would probably return in the next patch, allowing you to punish the boss and clear acid on later waves (8+).
(19:23) Gnomonkey says the spot where the rock block drags the Doom of Mokhaiotl to the middle of the room is a perfect location to clear acid with the holy water punish, and the tech should also work with it once patched.

Doom of Mokhaiotl: slam and stalagmite orb

(19:23) Gnomonkey says the rock block drags the Doom of Mokhaiotl to the middle of the room, which makes the orb phase easier because stalagmites spawn on both sides, giving a big section of the arena to dodge with the orb.
(19:56) Gnomonkey says developers stated the orb will clear poison and that the orb now stays if you kill the boss as the stalagmites spawn, so you might be able to set it up after the boss dies to clear acid or poison; he says it is possible but unconfirmed.
(23:29) Gnomonkey says he got only four orb phases in 23 delves of the Doom of Mokhaiotl using this tech.

Gnomonkey

(10:56) Gnomonkey describes a clean Doom of Mokhaiotl run as a wave 23 completion, with the footage from about cave 16.
(23:29) Gnomonkey says he had gotten nothing except a pet in 1200 Doom of Mokhaiotl clears at the time of the video.
(23:29) Gnomonkey credits Hedron for labbing many of the rock block tiles and says he will make budget guides for the Doom of Mokhaiotl after the next week's bug fixes.