Missing Background in Magatia

If you grind in Magatia in 5x-6x, you may have seen this anyway, but here you go.
If you look at pictures in KMS of Lab C-2, you see this:
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(Yes I stole it but that's not the point!)

That green tank is not in our C-2. Nexon, when you c&p, make sure that everything is in it!

(Oh if this is the wrong section, could it be moved please?)

It's not a background, it's a reactor.

Every once in a while, a bot-catching monster (probably Deet + Roy, not sure) spawns there. If you hit it, it'll send you back to town.

When it spawns, you can hit the reactor 5 times in order to weaken the monster (basically seal it so it can't use its return-to-town attack), then kill it normally.

There's other reactors like this, such as the one at Coolies (when Lich spawns, drop an etc item on it or something like that to weaken it).

Edit: Also, we don't have C-2's bot catcher atm.

The bot catching monster at that map is Rurumo but yeah. That's the reactor to get rid of it. You have to hit it until all the levers are down, then it lets out a gas that seals the monster.