you're really over-complicating the changes needed for no reason, increase the chance of higher rank nebs from neb boxes, make neb boxes drop A LOT more often maybe even have them purchasable from some shops like the crusader coin shop. make fusing nebs NOT cost nx + make it so everything up to A rank Can't drop down a nebulite rank, bring back alien cubes. Implement S ranks however make it so they can't be alien cubed and if fused have a chance of dropping down to A rank. make it so bosses drop special neb boxes that will give a b rank or a rank neb.