Paradox Junction has a way of turning a "quick run" into a full-on project, especially once you decide you want the Sundergat. If you're still learning spawns or trying to tidy up your aim, running a CoD BO7 Bot Lobby for warm-up can make the early setup feel way less chaotic. Either way, the upgrade doesn't care about your confidence—it cares about steps and spacing. Miss one detail and you'll be waiting around for another chance while the rounds get uglier.

Build the base Blundergat first

You can't skip the foundation. Before anything "Sunder" happens, you've got to craft the Blundergat from the four parts around the map, then assemble it at the Cul-de-Sac workbench. It's the plain wooden bench with the vise—easy to jog past if you're not looking. A lot of people waste time trying to force the quest without it. Doesn't work. Get the shotgun built, buy yourself breathing room, and keep that bench location in your head because you'll be coming back to it under pressure.

Use the blue-flame tornado zombies the right way

After rounds start rolling, you'll notice a special type turning up at the end of a wave: zombies wrapped in a blue, tornado-like flame effect. They sound different too, kind of a sharp crackle cutting through the usual noise. Here's the part that trips teams up: don't delete them the second you see them. You need to do this in order. First, bait one all the way to the Cul-de-Sac workbench and kill it right next to the bench with the Blundergat. Second, repeat that with another blue-flame one, same spot, same weapon. If you're even a bit too far out—like "close enough, surely"—it often won't count, and you'll be stuck waiting for the next end-of-round spawn while everyone gets impatient.

Trigger the Mimic, then play the timelines

Once the second blue-flame kill registers, a Tortured Mimic shows up, and it's not a paper target. Keep moving, don't get cornered by your own greed, and finish it off at the bench as well. After that, you're basically dealing with Paradox Junction's split reality. You need to reach the Past version of the map (wait for the shift or pay for the golden portal), find that same workbench in the Past, and smack it with a melee to interact. Set the Blundergat down there, then head back into the Present timeline and check the bench area—the change is what you're here for. While you're doing all this, Rad-Hounds are the annoying wildcard; their radioactive pop can ruin your spacing, so don't kite them through your work area.

Squad habits that save the run

In co-op, the quest isn't hard because it's complicated—it's hard because somebody always "helps" at the wrong moment. Call out the blue-flame zombie the second it spawns and tell everyone to stop shooting near Cul-de-Sac until it's done. Also, keep a little essence spare so you can force a Past trip instead of waiting around while the map decides for you. If you're short on time or just want your setup sorted faster, plenty of players top up essentials through U4GM so they can focus on the timing and the bench plays instead of scraping by round to round.