[further reading: https://www.guildwars2.com/en/news/encounter-design-tabletops-and-chess/] #GuildWars2

Mursaat Overseer is a raid boss with 30 million health and no attacks. It doesn't do anything. It will slowly follow whoever picks up the Claim spell, and that's it.

... so how is this a raid boss, exactly?

The floor.

The boss arena is a 4x4 grid, with 8 brown (safe) tiles on the side you start on and 8 orange (danger) tiles on the other side.

The orange "danger" tiles deal 3500 damage per second to players who stand on them. (For reference, player max health ranges from 10 to 50 thousand, with the vast majority of raiders near the lower end of that spectrum because you build for damage dealing, not health.)

Enemy pieces that move onto a tile capture it and turn it orange; the player with Claim can turn an orange tile brown every 8 seconds.

Yes, enemy pieces. There's more than just the overseer.

There are also Jade Scouts, which slowly move from the enemy side of the board to the player side. They have shields, which make them completely immune to damage unless the player with Dispel removes them (Dispel can be cast every 18 seconds, and the shields come back after a while).

Killing a Jade Scout stops it from moving, but it regenerates its health where it stands and then continues its march down the board. If a Jade Scout reaches the end of the board, it becomes a Jade Soldier, which deals pulsing damage, applies debuffs, and follows the player who picked up Protect. They also continue to regenerate their shields and capture tiles they enter. If a Jade Soldier is killed, it teleports back to the start of the board and becomes a Jade Scout.

But I said that the floor is the raid boss. What else can it do?

Every 30 seconds, green spikes appear in a pattern on the board. If you're standing where those green spikes are when they trigger a few seconds later, you die. It doesn't deal damage. You just die. Regardless of what your health was, or whether you had evasion or whatever.

The only exception is that the player with Protect can summon a bubble that makes people inside it immune to damage and the spikes. They can only do this once in the entire fight.

The pattern changes to fill up more of the board for every 25% of the Mursaat Overseer's health.

But here's the best part: Challenge Mote doesn't just bump the boss's health from 22 to 30 million. It also adds yet another floor mechanic.

Every 30 seconds (initially synchronized with the green spikes, but the green spikes reset their timer when the boss reaches multiples of 25% health), four tiles light up blue. There is only one pattern, but it can be rotated four ways.

After 4 seconds, if you're not standing on a blue tile, you die. The bubble can't even save you from this.

And the best best part: the blue tiles are rotated separately for each of the 10 players. You can only see which tiles are safe for you, not any of the other nine players in your squad.

After 6 minutes, the person with Claim loses the ability to Claim and all damage is doubled, so you're probably going to lose shortly after.