I’ve seen people mention Larloch having a deal with Mystra that allowed him use of 10lvl magic – was this true?

1)
No, it’s not true. As in: Larloch has a deal with Mystra about what he won’t try, so she’ll leave him alone.
Larloch has many, many liches serving him, so formidable massed power of arcane magic he can direct. He’s also studied more magic, and for longer, than. 2)
…almost all living mortals, and so knows alternatives to the Weave = ways around Mystra. So he can work truly mighty magics in other ways. Which is why the Srinshee snatching him out of the Realms with her.#Realmslore

— Ed Greenwood (@TheEdVerse) March 11, 2020

So how would he work as a warlock patron? Badly, considering he’s out of contact with the Realms right now. And quite possibly with continued existence. I’d not want to fight toe-to-toe with the Srinshee.#Realmslore

— Ed Greenwood (@TheEdVerse) March 12, 2020

The big battle at the end of THE HERALD, the final novel of The Sundering Saga. Some dramatic things happened. ;}#Realmslore

— Ed Greenwood (@TheEdVerse) March 12, 2020