Critique This Encounter

[MortalPlague]

I'm designing an old temple inhabited by two separate factions, one of which is a tribe of lizardfolk. This is my gatehouse encounter. I'd like to get a little bit of feedback on a few ideas I've had for this particular combat.

My party is five adventurers who will be 6th level by the time they get to this. We have a Goliath Fighter, a Dwarf Druid, a Half-Elf Sorcerer, a Human Warlord, and a Half-Orc Rogue, assuming nobody dies by the time they reach this encounter.

The Colonnade - Level 7 Encounter - 1550 xp

The lizardfolk have two major entrances to their section of the temple, and this is one of them. Two of the pillars on the northern wall collapsed, partially blocking the way into the channel, making this an even better defensive position. These broken pillar sections fall into impassible (red) and difficult terrain (orange). The structural damage isn't limited there, however; the steps at the far end have also been reduced to rubble; a DC 15 athletics check or a full move action are required to mount the platform (5 feet up). The side walls are slick with slime, and at the top an overhanging lip makes the climb considerably more challenging, requiring a DC 25 athletics check.

The lizardfolk have positioned three archers (Gnoll Huntmasters, reskinned) and a Greenscale Hunter (who will jump down to flank when possible) among the columns. Down below, three more hunters and a Blackscale Bruiser stand guard. On its own, this force, with the defenses in place, should prove a decent challenge. But to add spice to the encounter, whenever the Blackscale Bruiser misses an attack, the strength of his blow cracks parts of the floor, and 1d2 centipede swarms (MM2) join the fight, attacking at random. Once the centipedes become enough of a threat, the lizardmen will retreat up to the platform and attempt to keep the adventurers down in the pit with the centipedes.

Here's a map of the encounter area. I haven't yet filled in the rooms surrounding, but I don't plan to have anything that will spill over into this fight. The triangles represent the reskinned Gnoll Huntmasters, the dots represent the Greenscale Hunters, and the big square is the Blackscale Bruiser.

Thoughts?

[DanmarLOK]

Seems good to me, I like the centipede swarms. I might offer to have the bruiser push or smash pillars that then do a line based aoe against reflex, perhaps with a negative to hit mod or make it so that any miss against an opponent next to the columns has achance to knock one down *pictures the archers above suddenly flailing their arms and falling to their doom as the bruiser knocks the column out from under one and the subsequent player reactions*

[MortalPlague]

Thanks Dan. I've done the falling pillars thing in the past, and it's worked very well. I may have to do that here too.