Synergistic Monster Ecology - 3 Devious Monster Pairs Working Together
Monsters don’t exist in a room, by themselves, twiddling their thumbs (or pseudopods) waiting for adventurers to break down the door, slay them, loot all their valuables, and move on to the next room. In dungeons, these monsters perform a unique ecosystem, only interrupted when a barbarian rages and empties the dungeon of all living and un-living monsters.
But what if they had friends to watch their backs and increase their power?
Devious Monster Pairs
These 3 monster pairings show how you can combine monsters to create unique monster interactions, create a single boss out of two weaker monsters, or create an unforgettable encounter.
Simple Rules
When using these monster pairs, treat them as two separate creatures that occupy the same space, and when one moves, they both move at the same time.
For targeting with spell effects that deal conditions, you will have to decide if it makes sense for both or only one of the creatures to be affected by it. If you decide that both would be affected, make only a single saving throw and use the highest save for either monster in the pair.
In addition, they gain two turns in the initiative with each monster getting its own turn.
You keep their stat blocks separate, but only one of the monsters can be damaged at first. Once that first monster’s hit points are depleted to 0 hit points, they separate with the first monster dying and the second continuing to fight.
A monster pair might separate before the first monster is dead if the party has a plan to split them apart.
Flameskull and Helmed Horror
In this encounter, a helmed horror (or animated armor for a lower Challenge Rating) and a flameskull have created a flaming, terrifying bond. The flameskull is safely encased within the armor of the helmed horror, peering through the helmed horror’s helmet.
The flameskull will stay inside the helmed horror until it is defeated. Once the helmed horror is defeated, the flameskulls rises out of the defeated armor. For additional synergy, the flameskull is still wearing the helmet, which grants it a small +1 bonus to its Armor Class.
While the helmed horror is alive, it gains immunity to fire damage, so the flameskull does not hurt the armor with its fire spells.
Skeletons and Oozes
This unique duo combines the structural integrity of a skeleton with the soft, caustic jelly of an ooze. Which one you choose depends on what CR you want, might I suggest a black pudding or a gray ooze?
The skeleton fights from within the ooze, unable to be targeted until the ooze on the outside of it is destroyed. The skeleton still wields any weapons, or makes its attacks as usual, its skeletal claws lashing out from the ooze. If the ooze is large enough to hold multiple creatures within it, like a gelatinous cube, the skeleton could directly attack whoever is consumed, and be attacked directly as well, before the ooze is destroyed.
Ghost and Humanoids
This is not like the typical possession, as the humanoids or NPCs also get a turn in the initiative. This duo is more like the ghost is empowering the humanoid, not forcing the humanoid to go against its wants or needs like a summoner, or from pop culture like Kill la Kill or Venom from Spiderman.
In this situation, you may want to re-flavor the ghost as a possessing spirit or daemon that grants additional powers or abilities, not just an undead horror.
In addition, the ghost can not be destroyed until the humanoid it possesses is first defeated, at which point the ghost rises out and can be defeated. While the ghost resides within its host, it can still use its withering touch, but you may also give it the power to make ranged, telekinetic attacks like a poltergeist or give it a handful of spells that you reflavor to better match a possessing spirit.
Even More Combinations
There are many combinations you can make with the available monsters to create unique mixtures, and they don’t all have to be set up in the same way as these are.
For example, you could have a group of goblins riding a giraffe into battle, and you could set up the goblins as a ‘swarm’ of goblins (using our swarm template). When the goblin swarm takes damage, you describe the goblins falling off the giraffe. (In this situation, you could let players target either creature.)
Do you have a favorite combination of monsters? Share them below!
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