None of the stock aWoD Sorceries really fit a celestial character, I think. For the celestial, I ended up thinking up a "Litanies" discipline, where he could start up a chant that did stuff, bard-style, and could extend them as a free, or maybe simple action. The discipline's passive effect would make the user's voice carry clearer, further, over louder noises. The first power I thought up was a "Litany of Unity", which'd make a sort of hive-mind for the hearers, that intuitively let those hearing it know when others needed them or whatever, making them work like a "well-oiled machine".
Also for the one, it reflected the character turning into a googirl - resilient, shapechanging, and made of horrible acidpoisoncrap. I'm not so sure what to do about it's passive effects, but I'd think +1 to death threshold (which uh I assume is used when you're KO'd with all lethal wounds and determines if you die?), +1 survival, and maybe +1 to resist acids, poisons, and diseases. Though, most of the powers give outright immunities anyway, and thematically gaining immunity to poison when you start producing poison is pretty alright, too.
Instead of from scratch, I sorta just glued a bunch of stuff from different disciplines together. Basically, basic = Lure of Destruction's basics. Advanced = Abyss of the Body (diseases! Magic ones, especially. That's kinda like poison, right?), Blood of Acid, and maybe stuff that uses water, like Water Prison, refluffing it to say it uses your body/slime instead of any old pool of water. And Elder - which would require Total Viscosity, at least? - could give you Giant Size and maybe some powers that let manipulate your body - making it hard and sharp like steel, denser or lighter, hotter or colder, that sorta thing. Also splitting yourself into clones regular slimes or whatever. Basically, elder level turns you into a
Queen Slime, except not handicapped with super-bloat, maybe.