There is another really simple solution.
Require crafted items to be "paid" to the OP to keep it.
If a payment period ends and not enough or no payment received, TH drops double points. At TH0 it becomes ownerless and the next guild can fight only NPC for it then pay a craft penance to initially hold it.
Introduce a new crafted item for every craft branch that is not tradable that the OP requires.
Require crafted items to be "paid" to the OP to keep it.
If a payment period ends and not enough or no payment received, TH drops double points. At TH0 it becomes ownerless and the next guild can fight only NPC for it then pay a craft penance to initially hold it.
Introduce a new crafted item for every craft branch that is not tradable that the OP requires.
---