And when they inevitably dry up or freeze to death? Or explode instead of freezing when that area drives them crazy.
Explosive Slug Slime
Explosive Slugs were modified from one type of slug that exists in the desert from the Mad King's rein. This slug has a defensive measure of igniting in an explosion when hit with kinetic force. This is in fact due to the slime that permeates their bodies, and this slime can be harvested to grant arrows an explosive fire property of their own.
This slime simply goes off when hit with any amount of kinetic force. stabbing it gently and squeezing it out won't set it off, but going full force most definitely will. Another thing is these slugs tend to live under rocks, only traveling during the night, and eat sand which they turn into slime. The slime they produce keeps them hydrated even in these harsh conditions..
Coat an arrow with it, or use a glass container with the stuff to sling, both work for generating the explosive force. The latter is significantly more powerful than the former though. For the former, a small iron jug is used so it can be applied when needed, or thrown as an improvised grenade.
Do not drop containers of the stuff, and always clean tools used to handle it afterward.
This design gives us explosive slime, which we don't need to keep alive. Well, other than breeding the slugs for their slime. And will be applied to our units as is, giving all the units the option to use it for their arrows and slings. Plus not needing a research action in the first place, as it produces a product for use.