Bee Wax

Nothing else in the game produces this, and you cannot buy it, so every piece of gear that wants it is gated behind going back to the hive. Kitting yourself out in the full bee set and picking up the summon staff will not happen off one kill, so build the arena somewhere you can return to instead of tearing it down after the first fight.

Queen Bee hands you a pile of grenades alongside the wax, and those grenades were made of wax in the first place. Once you have Shimmer access you can throw the leftovers back in and recover the material, which turns a stack of ammo you were never going to throw into progress toward the armor. Sell value on the raw material has always been poor, so if you end up with a surplus you are better off crafting it into something first.