This is a big question mark in my timeline, we know that BG:3 is a "sequel" to Descent into Avernus, Elturel is maybe a week or month Returned, when we start. We also know that Devils attacked Thorm, ??? We have a Cambion interested in our tadpole (or something else related), we have a githyanki device, that I for some reason think has an infernal connection (did it have infernal runes at one point?) , one of our companions will be an escaped lieutenant of Zariel (and our tadpole vision seems show she has a special connection to her) and of course Wyll has a pact with Mizora.

Most of our main characters already have some tangential connection to the main plot (...leaving out Tav... rolleyes) Shadowheart is a Sharran who was sent to take the Artifact, Lae'zel is a Githyanki see: Artifact, and Gale, though we don't know much about him, has some clear connections to Netherese magic, which we know is at play with the Tadpole. That leaves Wyll and Astarion, Wyll has an infernal connection being a Warlock and because of Mizora who's been taken to Moonrise (I should add a list of people taken to Moonrise) so really that Leaves Astarion, how can we fit him in? His master is a vampire, Cazador, who wrote, in Infernal, something on his back, a contract? a contract related to the Absolute, Zariel, Elturel or maybe the Artifact?

In FR lore I forget who the Vampire Hellknight is (it was retconned for the module anyway, I think) but he shows up during Descent doesn't he? Hmm I think that's a dead end but what else can you think of?

I'm also curious how they're going to deal with the resolution of Descent into Avernus, most people I imagine would expect Zariel to be redeemed at the end.