Including the setup, monsters, tactics, outcome, etc would be awesome.
1. Clocktower approx 50x50 square, stairway (5ft wide) leading up along the walls with platforms at each corner that were 10x10. (This was a late heroic tier encounter....higher levels this would be easier...flight, multiple teleports, etc)
Setup:
- Bottom level - 1-2 Large Brute (sorry don't remember specific monster).
- 1st platform - 1 soldier
- 2nd platform - 1 soldier and 1 skirmisher/lurker
- 3rd platform - medusa archer
Tactics:
Archer picks away at the party while the rest of the monsters serve as blockers and cause damage. The monsters were positioned to guard the way up to the next level and prevent the party from making their way up quickly. They were deployed to be a delaying force while the final encounter waited above on the next level. The archer has light cover from ranged attacks.
Outcome:
The battle was rough for the party. No deaths but plenty of bloodied characters and healing needed. The large brutes needed to be kept busy by the defender and healer which forced the other party members to charge up the stairs and get onto the platforms to get at the monsters without the support of those two critical party members. All the while, the archer is plunking away every round hurting targets of opportunity...and focusing on anyone making their way up the stairs.
Worked out very well and was challenging. Easy to tune to any party by varying the difficulty and number of defenders.
2. A large trapped room whose insides were built entirely from ice structures (ramps, walkways, platforms). As soon as the party entered the room, the trap was sprung--two large, metal dragon heads start spewing jets of flame every few seconds into the room, causing the ice to slowly melt. In addition, the outer doors slam shut, sealing the party in. The goal is to get to the top platform and retrieve an item from a chest there. Several monsterous defenders wait along the way, and at the top to stop the party. (Effectively this was a timed combat...every round or two the penalties for moving on the slick ice increase slightly, until at a certain point the structure begins to disintegrate entirely.)
Setup:
Mid-way up:
- 4 - Gargoyles - planted in alcoves in the wall.
Top: (guarding the chest)
- 2 lurkers/skirmishers
- 1 controller
- 1 soldier/leader
Tactics:
The Gargoyles were relatively hard to spot and would come out when the party got near. Their main purpose was to slow the party down, or cause them to split up. The monsters at the top will fight to keep the party away from the item--and attempt to use the slick terrain to their advantage, including pushing players down so they would slide back down.
Special properties:
- Ramps were configured with slight slopes to ensure things would slide down them.
- Skill checks could be made to allow the player to travel normal speed over the icy terrain. Skill DC relatively easy. Failure means they couldn't treat it as normal terrain and didn't move as far. As the encounter went on, the DC went up (ice melting).
- Skill check could also be made to allow the player to run and not fall prone at the end of a run. Higher DC, higher risk, higher reward in terms of movement through the room.
- Slides/sliding: a sliding character or NPC would generally slide some amount...say 1d10 squares (usually prone) down the icy ramps. They could then make a check to stop the sliding. Stopping a slide could also be done by having another party member spending an action to grab a party member that was sliding past.
- The party has roughly 10-12 rounds total to retrieve the item and escape the room through an alternate door that becomes apparent once they reach the top.
- Characters falling into the freezing water below would be subject to penalties - could use endurance to avoid this....and of course would have to try and make it back to the top in time.
Outcome:
This turned out to be not only challenging for the players but a lot of fun. Since it was part combat, part skill based, it allowed them to do a bit of both, without penalizing them too heavily if they didn't have the right skills. The players used the ice to their advantage and were able to muscle a couple of the defenders away from the chest and cause them to slide/fall to the bottom. The monsters were also able to knock a player or two away (in one case knocked one player into another like a bowling ball...causing both to slide away). In the combat I ran my players actually were not able to make it to the upper door, one or two of them had fallen down, so they all went back down and forced the doors using their combined strength.
Easy to tune this encounter from the height/pathways in the room, to the number of rounds the party has to solve it, to the number and types of defenders fighting back.
On the battle mat drew this as three separate levels, bottom, mid, top, with both ramps and pathways going in multiple directions (it was symmetrical). Arrows to indicate the end of one level and start of the next. This allowed the party to choose their path and they could cross over to the other path on the mid and top levels as needed.
Both of these used one or more of the types of terrain mentioned in the DMG...if that is what you were referring to specifically. #1 you could say loosely uses blocking and cover terrain (channelling the party up a specific path, allowing the archer a good position that could not be easily hit). #2 used challenging and difficult terrain.
Pretty much, the scene looks like a baseball diamond. The rat is on home plate on a small island up against a stone wall surrounded by an acid moat. He starts out shooting acid balls towards the pc's.
After a few rounds he runs out of ammo and starts attacking with melee. His minions would be dead by then presumably.
So picture a baseball diamond, put a stone wall around it, put an acid moat in front of the home plate, and there ya go.