As an instance I am a cleric of Mystra, and I want her assist, so I forged Planar Ally:
You beseech an otherworldly entity for support. The being should be recognized to you: a god, a primordial, a demon prince, or another being of cosmic energy. That entity sends a celestial, an elemental, or a fiend loyal to it to help you, making the creature seem in an unoccupied house inside vary.
When the creature seems, it’s underneath no compulsion to behave in any explicit manner. You possibly can ask the creature to carry out a service in trade for cost, but it surely isn’t obliged to take action. The requested activity might vary from easy (fly us throughout the chasm, or assist us battle a battle) to complicated (spy on our enemies, or defend us throughout our foray into the dungeon). You have to be capable of talk with the creature to discount for its providers.
Cost can take quite a lot of kinds
My godess sends a Deva with siverfire wings or one thing like that to assist me with a activity, and I ask the angel to only keep nonetheless and quiet for 1 hour. Then, I begin casting Planar Binding:
With this spell, you try and bind a celestial, an elemental, a fey, or a fiend to your service. The creature should be inside vary for all the casting of the spell. On the completion of the casting, the goal should make a Charisma saving throw. On a failed save, it’s sure to serve you for the period. If the creature was summoned or created by one other spell, that spell’s period is prolonged to match the period of this spell. A sure creature should comply with your directions to one of the best of its capacity.
Would I be capable of management the angel in opposition to my godess’ will with out paying the price of the planar ally? What occurs if I forged the binding at ninth stage, would I get a messenger of Mystra at my service for one 12 months, or solely till the angel compleats its first activity?