Plane of Air: I remember going there a long time ago, pre-wipe so I don't have a primary account on this besides a few personal observations. First, I notice no-one goes there. I've been with parties who've gone to Dwarf Home, Earth Plane, Plane of Shadows, Fire Plane, Water Plane, and just recently the Halls of the Dead. Minielvis told me it was too little the xp for too much the trouble.
This seems to be the main problem. Too little xp for too much the trouble. On a different game I play, they call it "Developer Disease." Whenever a developer is designing an area, and re-designing it over and over, they often remain blind to several areas of play considering they know EXACTLY everything about it because they designed it. Whenever a play-tester comes along, however, they die in a few seconds.
Dwarf Home: Actually pretty balanced, only problem I found here was that the gear drop rate is EXTREMELY low. For six levels we found not one Holy Plate. I also have heard that a few of the Dwarven crafted items don't drop much either.
Earth Plane: Easiest planes, hands down. But its even considering the CR is pretty low, a fair trade-off. Gear dropped on a good level, nice work with Grindstones and Stalagmites.
Fire Plane: Only been here once post-wipe. It doesn't seem to be too popular with parties. I didn't notice any problems there myself.
Water Plane: Oh god. So hard it was insane. Dwarven Defenders are known for being really good tanks, apparently not here
Plane of the Shadows: Drops were scarce on the Shadar-Kai, but that makes sense and I'm assuming is supposed to be that way. Only problem we found here were Shadow Renders and Nightstalkers were definitely not worth the CR.
Halls of the Dead: Ah, the new plane. We went there, and let me tell ya, it was scary. We handled the outside place pretty darn well. XP was pitiful, but we didn't die (actually we died several times but by die I mean we all die). 30 xp at level 36 made Baby Reznor cry. The whole time we were there, I got 3k xp. We were there for a while. The Midget Skull Reapers had ungodly AC despite the fact they were dual-wielders. The archers were retarded. Half of them didn't shoot there bows. What they DID do however, was a bolt attack that knocked you down for what seemed forever. That needs to go or be fixed in some way. A bolt attack from a CR 29 creature should not knock down a pure level 37 monk with 84 discipline. Then we got into the Halls of the Dead. Spell Failure all around, which normally wouldn't be a problem but my mates got cursed or something and I couldn't do any restores. Then Sandy died, tried a resurrection, and it didn't work. We all died.
Yeah....I think I'm done typing now.
Edit: Fixed typos




