Help planning a challenging encounter (3.5)

[gallagher]

so i have a map created, some sort of dungeon if you will. it is consisting of about 10 levels made up of 9 rooms each (8 smaller perimeter rooms and 1 large central room in each level with a method of ascending and descending in the middle rooms).

i want to fill this thing with zombies, with the end of this dungeon being an even harder undead encounter. they will be fighting to continuously get lower and lower in the earth until they fight a final zombie which should rid area of this problem.

what are some good corporeal undead to throw at these guys? and some good ways to keep it challenging. the party consists of a 3 man team, all level 10
-a Bearbarian
-An archery swift hunter build
-a homebrewed beguiler-warmage mix.

the caster throws me for a bit of a surprise, as i am not sure what to expect out of him. he is the type that enjoys a bit of reckless abandon (role-plays it well too, better than the barbarian).

with that in mind, if anyone can point me in the right direction, what i am looking for is some good enemies to fight (and hopefully have an encounter in every room, but without it getting boring, so a lot of variety), some natural traps (slippery residues and the whatnot, ways to make it hard to get around or slow them down) and of course some good loot!

any help is greatly appreciated

[AslanCross]

Some interesting, flavorful undead:
1. Boneclaws (CR 5; MM3): Large, extended reach strikers.
2. Bonedrinkers (CR 6, MM3 ; Lesser Bonedrinkers are CR 4) have a terrifying ability to do CON damage when they grapple. Plus, they're undead bugbears with tentacles.
3. Plague Walkers (CR 3, MM4): Exploding zombies!
4. If you really want to go with the "boss encounters may be up to 5 CR over the party level," the Charnel Hound (MM3) is a CR 13 Huge undead; a giant hound made out of semianimate corpses.
5. There's also the Necronaut (MM3), but at Gargantuan and CR 14, it might be far too strong. IIRC it also has over 400 HP.
6. Ravenloft Zombies (CR 2): Much tougher than the garden-variety human commoner zombie, and they can move and attack.
7. Necrosis Carnexes (CR 3; MM4): Horrid amalgamations of undead flesh that heal other undead.
8. Dust Wights (CR 7; MM3): The undead remains of an Earth Elemental. Slowly rusts away metal objects it touches, and its cloud of dust slowly petrifies people.
9. Brain in a Jar. (CR 3; LM): A brain. In a jar. A psychic brain in a jar. Add Psion levels.

[gallagher]

Some interesting, flavorful undead:
1. Boneclaws (CR 5; MM3): Large, extended reach strikers.
2. Bonedrinkers (CR 6, MM3 ; Lesser Bonedrinkers are CR 4) have a terrifying ability to do CON damage when they grapple. Plus, they're undead bugbears with tentacles.
3. Plague Walkers (CR 3, MM4): Exploding zombies!
4. If you really want to go with the "boss encounters may be up to 5 CR over the party level," the Charnel Hound (MM3) is a CR 13 Huge undead; a giant hound made out of semianimate corpses.
5. There's also the Necronaut (MM3), but at Gargantuan and CR 14, it might be far too strong. IIRC it also has over 400 HP.
6. Ravenloft Zombies (CR 2): Much tougher than the garden-variety human commoner zombie, and they can move and attack.
7. Necrosis Carnexes (CR 3; MM4): Horrid amalgamations of undead flesh that heal other undead.
8. Dust Wights (CR 7; MM3): The undead remains of an Earth Elemental. Slowly rusts away metal objects it touches, and its cloud of dust slowly petrifies people.
9. Brain in a Jar. (CR 3; LM): A brain. In a jar. A psychic brain in a jar. Add Psion levels.

charnel hound is perfect. with monsters in place, i was thinking that the treasure is actually leftovers from corpses. it fits thematically.