Gladiator of Sil'dih - Hateful Visage

The gladiator will cast Hateful Visage, which will summon iron statue heads that will shoot beams across the direction its facing while effectively splitting the arena by 2x2. This is followed up by Wrath of Ruin, which will summon orb sets that will fire off line AoEs in a grid pattern across the whole arena. Finally while all the mechanics are resolving, the gladiator will use Nothing Beside Remains to target all players with a targeted AoE attack, which means that everyone must spread out.

The iron statues will split the arena in quadrants, so you can assign each player to their own quadrants in order to utilize the maximum amount of space while spreading out. You might notice the statues shooting a gold or silver laser, but ignore those colors for now, because getting hit by any lasers is bad during this mechanic.

First, spread out to your own quadrant as agreed verbally or in the macro. Nobody else should be in your quadrant, as that would complicate things when you have to spread out.
There are always two statues that will each fire a laser in a quadrant, which further splits a quadrant into another 2x2. Identify which statues are opening fire into your quadrant and relocate into the safe tile.
The boss will now cast Wrath of Ruin, which summons orbs at the walls that will fire line AoEs in a grid pattern. This further reduces your tile to another 2x2.
Once the first set of the line AoEs resolves, you should then immediately move diagonal of your safe tile to dodge the other line AoE. Nothing Beside Remains should resolve and assuming everyone remained in their own quadrant, there should be no accidents.