Some good scug combo ideas for Rain World co-op:
Saint and Gourmand. With the piggyback feature, the Saint can pick up the Gourmand, use their tongue ability to get high up, and yeet the chonker down at any enemies for an aerial attack.
This only works if Spearmaster's weapons can be turned into explosives, but I'm pretty sure they can so this works pretty well. Spearmaster makes infinite spears, which means infinite explosives for Artificer as long as there is food.