Seeking some interesting CR7 Dungeon encounters

[Sticknia]

My party is headed in to a HUGE dungeon delve as part of an on going campaign.
I need some interesting filler to make up the parts of the dungeon that aren't part of the story line.

I'm looking for CR6 or CR7 and maybe a few CR8s to fill in some of the gaps. Traps, Combats, Riddles, Problem solving, etc.

Do you guys have any resources you use for this? Have any encounters that you have created that you adore and wouldn't mind me using?

I'll give you a cookie!

 

[Tinner]

Try a gang of four Violet Fungi. Individually, they're no match for the PC's, but with four attacks each, those Rot saves are going to add up. This comes out right around a CR 6, CR 7, probably a high 7 IMO. Don't use this unless your party has access to some Restoration spells/potions, or you will cripple them!

Four Giant Whiptail Centipedes also coems out to around the same CR. With their multitude of trip attacks, these can give a party a good fight too.

Three Phycomicds can beat up a party that can't handle acid and diseases.

Two or three Flail Snails can challenge the fighters and the spellcasters.

Don't overlook the importance of terrain to make memorable encounters. I harried a team of VERY high level PC's, by using fairly low-level archers. The archers were dangerous because their arrows were poisoned with a strength-sapping poison, and they ambushed the PC's as they were climbing down a very steep cliff. Having your STR reduced to zero as you cling to a cliff makes even low level monsters very deadly.

Likewise, a single troll can challenge this party of the troll can bull rush the PC's off a cliff-face. Fire immune monsters can lair inside rooms partially filled with lava. Put incorporeal undead inside a maze. The spectral monsters can move right through the walls, and use hit and run tactics to hound much tougher opponents. This works great with Shadows and their STR draining attacks!

Hope this helps.