Challenge Rating is equal to or less than your level, the binding powers of the scroll compel it to listen to you. You can then attempt to strike a bargain with the celestial, negotiating a service from it in exchange for a reward. The celestial is under no compulsion to strike the bargain; it is compelled only to parley long enough for you to present a bargain and allow for negotiations. If you or your allies attack or otherwise attempt to harm the celestial, the truce is broken, and the creature can act normally. If the celestial refuses the offer, it is free to take any actions it wishes. Should you and the celestial reach an agreement that is satisfactory to both parties, you must sign the charter and have the celestial do likewise (or make its mark, if it has no form of writing). The writing on the scroll changes to reflect the terms of the agreement struck. The magic of the charter holds both you and the celestial to the agreement until its service is rendered and the reward paid, at which point the scroll vanishes in a bright flash of light. A celestial typically attempts to fulfill its end of the bargain as best it can, and it is angry if you exploit any loopholes or literal interpretations to your advantage. If either party breaks the bargain, that creature immediately takes 10d6 radiant damage, and the charter is destroyed, ending the contract.