|Barbaric Gug Swarm|
I plan on using these only when the DC is missed by 10 and the die rolls a 1. If they're used more often than that the PCs will look like Keystone Cops, which isn't much fun.
|David knott 242|
The corresponding Starfinder deck had good rules for when to use it. I trust that this version will have equally good rules.
In the Starfinder rules, you had to be either not proficient with the weapon you were using or penalized by certain negative conditions to be at risk of a fumble.