These shouldn't be underestimated - I went in there at level 52 (bard), just wandering, and fell down a pit, and ended up being swarmed by 5 of these. I was rooted, and managed to charm one, mezz a few - but when charm broke I went ~down~.
Hmmmm That might be the reson why my group got whiped bad cuz we whent down the from FoB,to the main room one guy looked at the map and said hey just follow me down this hole to room2 ..leavi and invis(saying to our self hehehe The easy way down) we all hit the group at the same time and the 2 senconds later "EVAC EVAC".....well thy do see invis...and we hade to pull some friends in for the CR... Ohh Btw I got a cool dagger from the CR 7/20 dex 5
I just had a similar experience; we had a nice full group, all around L40 so we just dropped to room 2 thinking we'd kill everything in sight. Well, bad idea! There were about 10 spiders in there, and I dont even think we killed one of them. They kept healing each other, and I was dead before our druid could evac the party. I recovered my corpse by dropping down with lev and invis, then immediately went for the corner out of sight of the spiders. summon /corpse, loot, gate, done.
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Vaal Halen 115 Bard Council of Norrath Xev>Druzzil Ro>Xegony Server