Even though Disco Domination strongly suggested boogie bombing it turns out it's a variant of capture the flag, where the only difference is that Epic's new LTM requires you to emote on a dance floor. Oh and the quad launcher is here too.
As the rules of Fortnite's new LTM state, two teams of 50 players fight across the map, with respawning enabled until the last circle, i.e. the third one. Five disco floors will pop up across the map but only when the circles are stationary.
The goal is to emote on the dance floor until you've raised the disco ball, which captures it for your team. Note that the dance floor has to be cleared of enemies first and the more of your teammates take to the dance floor, the faster Fortnite's disco ball goes up.
A captured floor fills a team's dance bar, which is visible in the HUD, and as you'd expect, the first team to fill it up wins Disco Domination. Apparently, floors in later stages fill up the dance bar more quickly so, there's always hope if you're willing to bring it on.
There's a few goodies thrown in by Fortnite devs, like glider redeploying, which means no more fall damage if you can react quickly. Also, you can't build on or over dance floors, although you can build around them. Maybe you should realy recon
As for the quad launcher, it comes in epic and legendary variants, dealing 80 and 84 damage per rocket. Do we really need to say there's four rockets? The rockets sport a 300 unit explosion radius so yeah, Epic weren't kidding about blanketing the area.
Fortnite's Port-a-Fortress returns in the 6.02 update, after a lengthy absence but with a significantly lower drop chance. Speaking of drop chances, Epic improved the dropping odds for 10 weapons, including most snipers, the rocket launcher and legendary guiding missile.
As usual, the patch comes with a plethora of other tweaks and fixes, all of which you can find in Epic's official Fortnite 6.02 patch notes here.