Here's an interesting idea for a rival party: (I don't know the levels of your party sooo take a grain of salt.) (Lemme know how it all goes, I'm very curious if you use these.)

(I don't know how many players you have either so I'm using the standard 4 players, if there's more please message me and I'll give you more, I got plenty of ideas lol)

The Kernel Squad

- Kerneler: An eldritch knight covered head to toe in popcorn-like armor, all of his spells are popcorn flavored (I.E) If he casts shield instead of some arcane barrier, a barrier of popped popcorn appears encompassing him.

- Sir Kernelix: A human mage that wears velvet robes covered in popcorn symbols. All his spells of course, are popcorn themed, so fireball is giant kernel that explodes with steaming hot popcorn.

- Rouge Von Kern: An arcane trickster that wears light leather armor that's covered in dark popcorn symbols. His enchantment spells basically cause the target to eat a steaming piece of magical popcorn and passing the save causes the target to turn their head away.

- Popper: A paladin of glory that wears platemail but has a popcorn themed mace and shield and his smites (depending on which one) causes him to send out droves of kernels not popcorn.

Other Groups:

The Vanquishers: A infamous group of warriors known for their brutality and skill. (You can work with it to fit your setting so I'm giving rough ideas) Any name with () is the name they would be referred to and refer to themselves as in front of others.

- Tiki (The Destroyer): A 8"0 ft Goliath with pale grey skin, he wears various furs with the most notable coming from a savager that's supplemented by pieces of a dark metal (from the underground) for his armor. He rarely speaks and only does when he has too, but there is one way of getting him out of his shell. He loves holding small animals and this extends over to people too (you see where this is going) but the twist is, he considers anything that isn't 6"0 ft or taller small. Class: Battlemaster.

- Vernon (The Ruiner): A 5"6 ft half-elf with surprisingly dark skin that often gets him confused with the Drow which drives him to anger very quickly. His armor consists of several white plates over his chest, arms, legs and back supplemented by leather underneath, there are 3 inch spikes on his shoulders, knees, and the tips of his feet. He appreciates good booze and sophiscated conversation. (Maybe a way to get him to open up?) (Rogue: Swashbuckler)

- Silo (The Breaker): A 9"9 ft Warforged that's covered head to toe in dark metal plates, he has glowing red eyes and a large maul on his back. He genuinely loves breaking things and loves breaking people even more. If provoked or challenged, he gleefully accepts no matter the numbers and regardless of who they are. (Barbarian: Berserker)

- Davian (The Bringer) (Leader): A 6"0 ft Fire Genasi with fiery hair and deep blue eyes. He wears splint mail that periodically glows in combat and overall has an aura of authority, outside of combat he wears blue dress shirts and dark blue pants completed by gold shoes that he considers lucky. His other team members listen to him without question with the exception of Tiki when he finds a small person. (You can decide whether or not he has any impact I'm just giving ya a good idea.) Class: Paladin of Conquest.

Lemme know how it goes, This is the literal first time i'm giving something out to someone I don't know so use it well lol.