Slivers are creatures from Magic the Gathering that evolve from each other. One sliver gives all flying, one gives them more defense, one gives them more power, etc.
The hive mind monsters would be great additions to ICRPG. They could be insects, aliens, goblins, you name it.
So I broke them into 2 types of enemies.
Sliver Lords: Bigger than grunts and when killed all slivers lose a random buff. (1 or 2 Hearts)
Sliver Grunts: Low health grunts that always appear in swarms. (I personally make them have 1 HP)
You could have a battle with 6 Sliver Lords and a bunch of Grunts.
All slivers on the field have the following traits.
* Flying
* Power - bonus 1d4 damage - extra arms
* Armor - hard to hit
* Reduce damage taken by 1d4
* Ranged attack - up to far
* Spawns grunts when they get hit.
When a Sliver lord dies, all slivers lose one of the above buffs at random. Take out the lords or your gonna have a hard time.
You could even do this in reverse, and have no lords to start. And when a grunt dies another grunts turns into a Lord and gains resistance to how the last grunt died.
Grunt died to fire? Lord spawns and now they take half damage from fire or maybe immune to fire.
Grunt died from melee damage? another grunt turns into a lord that makes them hard to hit now.
Grunt died from area effect damage? A lord spawns giving them all flying.
Go crazy and have fun.