if the item creator includes a mutator contract when creating the item, it will have different possible tiers when crafted. the tiers are determined when crafted according to the element(s) the crafter placed in the wildcard slot. so the wildcard slot is required in that particular case.
we need to make this requirement more obvious in the ui, in the case of the pickaxe some people are confusing it for an optional slot and don't understand why they can't craft.
if the item creator includes a mutator contract when creating the item, it will have different possible tiers when crafted. the tiers are determined when crafted according to the element(s) the crafter placed in the wildcard slot. so the wildcard slot is required in that particular case.
we need to make this requirement more obvious in the ui, in the case of the pickaxe some people are confusing it for an optional slot and don't understand why they can't craft.