I’m assuming that you’re doing this with a raiding discord. (Pub halls?)
I would suggest doing it with a big group. The bigger the (mostly) better. During the fight, try to stick with the group. Its like a school of fish, the weaker ones/the ones towards the outside get picked off while the strongest and those closer to the heart of the group live.
One of my personal tips (that I use a lot) is to watch projectiles as they head towards the group. Try to give yourself a bit of anticipation as to when they’ll hit YOU, and judge accordingly. It takes a bit of practice to get used to it but once you get it down well, you’ll get hit by a lot fewer projectiles and rely a lot less on your priests.
A phase that i used to (and sometimes still do) nexus out at alot is the two key + drive by phase. That’s the one where the MBC first circles around the outer perimeter of the arena, and when enough damage is dealt, he spawns those two keys and those nasty drive-by rocks. It often gets really hairy here because you will have people scattered all throughout the edges of the arena, and a small group of players chasing those two keys. Whenever you see those rocks coming around, try to think of those colored shurikens as tentacles themselves. You’re probably not going to be able to dodge them all, but try to see where you can move through that line and into an area where its not shooting at. If all else fails… just dodge, and try to see where the most players are, as that’s probably where the heals (paladins/priests) are.
A bane of a lot of players are what most people call ‘pop rocks’. (Name means something, don’t scoff). After the second faze, MBC starts spawning these guys. They’ll float to a player, flash red and then pop. Follow the school of fish analogy I explained earlier, and you’ll almost never even get hit by them. But if they get close, literally just move like 1 tile. Its the difference between you taking 70-80 damage to you getting instapopped.