Aerial Unit R-21/X

Dropped by King Mechagon, the eighth and last boss of Operation: Mechagon, on Mythic difficulty and only when the dungeon's hard mode has been switched on at every stage: the first three bosses killed while the HK-8 Aerial Oppression Unit hovers over them, the HK-8 itself, the Robo-Waste pile clicked before K.U.-J.0., and the red button pressed before King Mechagon. One mount goes to one member of the party; by the players' figure the chance is 20% for each member that has not looted the boss that week. One try a week per character.

Chance 20% once a week, so about 5 tries on average — A players' figure, never published by Blizzard: 20% for each party member that has not looted King Mechagon that week (Wowhead comment of July 2019, a reply of December 2020, wow.gg, Warcraft Tavern), so 20% for one such player, about 40% for two and certain for five; Wowhead's guide says one mount is awarded to a random member of the party. Wowhead's own count (item page read 2026-10-11) is 519 mounts in 20,687 recorded loots of King Mechagon, the 2.51% of its tooltip, and 519 in 8,960 on Mythic (5.79%); both pool hard-mode kills with ordinary ones, which never drop it, so neither is a chance of anything

Inside Operation: Mechagon, a dungeon (Mythic)

Time there about 30 min a visit

Guides Wowhead: Operation: Mechagon Megadungeon Ability and Strategy Guide · wow.gg: Aerial Unit R-21/X · Warcraft Tavern: Aerial Unit R-21/X Mount Guide

• The way to Mechagon Island. The dungeon can be entered without the island's introduction quests; a character that has not done them flies across from the north-west of Kul Tiras · about 0.2 h
• Hard mode, switched on in four steps during the run itself. 1: kill each of the first three bosses (King Gobbamak, Gunker, Trixie and Naeno) while the HK-8 Aerial Oppression Unit hovers over that boss; it moves on after each kill, and the creatures around a boss can be cleared before it arrives. 2: the HK-8 fight then has a Tank Buster MK2 and leaves 55 seconds to overload the lit Overcharge Station before Annihilation Ray. 3: click the Robo-Waste pile on the left of K.U.-J.0.'s room before pulling it. 4: press the red button on the pedestal in King Mechagon's room before the pull; after a wipe press it again
• The red button's mechanic in the last fight: an Annihilo-tron 5000 counts down from 100 energy at 20 every 9 seconds and the party dies at 0. At 35 energy four Input Panels round the room light up one after another, and from 11 energy they have to be pressed in that order, within about five seconds; this comes round every 45 seconds. Wowhead's guide stations one player at each of the four panels. The first countdown runs out about 45 seconds after the pull, and no panel is ever pressed if the boss is dead by then

In all: about 0.2 h of play, starting from nothing.

/way is for the TomTom addon. Travel times are estimates: flying at 55 yards a second in a straight line and 30 seconds for a portal. A star marks a portal that needs a quest or other unlock done first.

The journal says only 'Drop: King Mechagon'; the hard mode is the whole of it, and it has to be Mythic: a 2026 comment warns that five tries gave nothing until the writer learned that. The wiki puts it as a 100% chance on hard mode on Mythic, which holds for a party of five that has not looted that week; a 2025 reply tells of two players finishing hard mode with no mount for the writer, which fits 20% a head.

The Heroic version is the dungeon cut into two halves, Junkyard and Workshop, entered through the Group Finder (wiki), while the hard mode runs through all eight bosses from the entrance in Rustbolt. The mount is the boss's loot, not the reward of the achievement Keep DPS-ing and Nobody Explodes, which the same kill gives (replies of 2020). If the fight is reset, the boss has to be pulled again with the red button, or there is no mount (a 2019 reply).

Sources disagree on how many players the Input Panels take:

• Wowhead's guide: five seconds are not enough to move between panels, so one player at each of the four
• Warcraft Tavern: two may do with movement abilities
• wow.gg: two or three can
• commenters of 2023 (boss dead in 49 seconds), 2024 and 2026 pressed the button and killed the boss before the first sequence

A 2023 comment (+166) describes another way round the panels: pull the boss out of the room so that he resets, pull him again the moment he is back, and the button can then be pressed late in the fight, leaving about 45 to 60 seconds to finish. Replies of 2023 say it worked; later ones were not found.

The HK-8 step is the one commenters call hardest: by the guide the station must be overloaded in 55 seconds, and Warcraft Tavern says more players at the station make it go faster. Comments of 2021 to 2023 get round it by running to Rustbolt while the ray is cast and back before the boss resets. Comments of 2024 to 2026 simply survive the ray (it took about 80% of a level 80 character's health) and finish the station afterwards, and one of 2025 says the boss reset instead.

The dungeon was shut to this route from late February to August 2025, while its Workshop half was in the Mythic+ rotation (comments of 2025, the latest of which has it back). The weekly lock is per character, as for the Mechagon Peacekeeper (wiki: Mythic dungeons have weekly lockouts).

The 30 minutes are an estimate for all eight bosses; wow.gg says 15 to 20 minutes with strong gear. The entrance coordinates are wow.gg's, as for the Mechagon Peacekeeper; the game's entrance table has no entry for this dungeon. A flying mount; the item binds when picked up and asks for level 10 (wiki). The same boss on the same hard mode gives an Azerite helm to one party member (Wowhead's guide).

Confidence in this entry: medium. Looked up in 2026.

Sources

• Wowhead: aerial unit r 21 x
• Wowhead: aerial unit r 21 x (comments)
• Wowhead: operation mechagon megadungeon strategy guide
• Wiki: X
• Wiki: Operation: Mechagon
• wow.gg: aerial unit r21x mount guide
• warcrafttavern.com: aerial unit r 21 x mount guide