Carl's crafting skill for soaking smoke curtains in potions to make novel magical tossables — unstable until leveled.
Infusion is the crafting skill Carl develops on his sapper's table, mixing Hobgoblin smoke curtains with potions to create new magically-infused tossables. Most attempts fail — a smoke curtain plus his drunken Rev-Up immunity smoothie just yields a blacked-out 'Dud' — but soaking one in an invisibility potion produces the Hobgoblin Disco Ball, raising the skill to level 3 (the system teasing, 'Just wait until you learn how to do this with vodka'). Infusing inherently destabilizes the product, so Carl avoids infusing actual explosives until his skill climbs high enough to remove that risk.
Many of his recipes are secretly copied from the Dungeon Anarchist's Cookbook and passed off as his own discoveries.
Carl's alchemical crafting skill for engineering custom infused smoke tossables.