When running an encounter or adventure, we often group monsters of the same type up with each other; a pack of Kobolds, a group of Grell or a flight of Dragons. (Wait..FLIGHT of DRAGONS? This is when you say FLEEEEEE…) If we do use other creatures in the encounter, it’s mostly because the manual will mention that they work hand in hand, like Goblins and Hobgoblins. Hobgoblins tend to rule over their weaker goblin cousins and make use of said goblins as expendable troops.
But we aren’t about standard stuff, are we? Dungeons and Dragons is such a varied and wide world, just about anything is possible if we put our minds to it.
What should you consider when teaming up an unusual pair of monsters?
I think it’s most important to consider the reason for the matchup. While this tends to be more for the intelligent creatures, monsters with goals in their mind, even those more beastial can have a reason to team up with a creature of a different species than itself.
Monsters, like people, have wants and needs. Sure, a lot of those needs are pretty basic, like how a griffon wants to eat horses, but a basic need is a need all the same, especially when it fuels the creatures to action.
Smarter creatures may think to team up with other creatures with similar goals, or who might have abilities they they don’t possess. It’s up to you as the storyteller to determine why these creatures are putting differences aside and working together.
Giving a reason for the matchup will give your players something to ponder if, and when, they have any downtime.
Example me this - Imagine you have a griffon living in a mountainous region. In that same region is a hill giant. Over the years the hill giant has attacked people along a nearby road and returns to its lair with all the spoils, including the horses.
He doesn’t care much for the horses but rather focuses on the treasure he gets. The griffon starts to see the hill giant as a source of food, as he’s constantly bringing him good horse meat to eat. So, finally, the people are fed up and hire a party of adventurers to rid themselves of this giant problem. When the PCs face off against the giant, they soon realize that they have a griffon to contend with, as the creature doesn’t want to lose it’s easy source of food; the giant. Suddenly, what the PCs thought might be easy money is a bit more of a deadly encounter. You might decide to leave evidence as to why this team up occurred; like having the players find the bones of the eaten horses strewn around the area, leading up to the griffon nest.
Sentient creatures are easier to set up; if their goals align then there is plenty of reason to have an accord.
You wouldn’t think that a lich and a harpy would be working together, but what if both were after the destruction of a certain town? The harpy, knowing she isn’t powerful enough to accomplish this herself, hears about a lich who wants the same thing. He’s working on a spell that will eradicate the town itself but, as all mages do, he needs spell components. Searching for said components always take away from important research, so the harpy tends to this task for him. They won’t necessarily have a relationship, but in the here and now, they both want this town destroyed and their alliance becomes one of convenience.
Those are some good in game reasons to have team ups; but what about out of game reasons? Why are you, the Dungeon Master, looking to create this team up?
Most commonly it’s to make an encounter more difficult, and that is a good reason. You want the PCs to be in jeopardy but adding more numbers of the same creature boosts the encounter level to dangerous heights, so you chose something a bit less challenging to make the entire encounter pack a bit more punch.
Alternatively, the matchup could help the PCs find a piece of information they need to further the adventure. In our example with the lich and the harpy, the harpy could be the clue that the PCs need to find the lich that the town has set them to find. The herb collecting harpy seems out of place so the PCs either follow her to the lich’s lair and the final battle ensues!
The next thing you want to look as is if the combination of creatures is a good matchup.
You wouldn’t want to try and rain destruction on a town with a fire elemental, who naturally sets things on fire and a water elemental, who tends to drown things to death. Unless you have something specific in mind, these two wouldn’t make a good matchup.
Back to the lich and the harpy; their abilities could harmonize quite well.
If the lich cast a spell that created some dangerous terrain between the heroes and the harpy, then the harpy employed her Luring Song, with unlucky rolls, the players might walk right into whatever trap the lich cast on the soil.
Regarding the giant and the griffon? The griffon could annoy the players with areal attacks while the giant hits them from the ground.
So keep those things in mind when you’re looking to create some crazy monster team and that Dungeons and Dragons is a wildly imaginative and diverse game; don’t be afraid to experiment with options!