When last we left the girls they were gingerly dealing with this maxxed-out dragon.
They grabbed some loot and went out into the hexjungle to find some means of dealing with the creature.
Which is always fun, right? You see a big bad and then the players, rather than turning it into one more disconnected episodic encounter, decide to move off and fight another day, keeping that looming threat in their mind. Like they're doing the foreshadowing for you.
So: back off into the irradiated jungles of Cobalt Reach.
Some very impressed goblins (we're at that neat point in the campaign, a few years in, where the players are 7-10th level and have some history and are obviously terrifying to everyone they meet) tell them their best bet for weapons is the rolling fortress of the Star Witch...
...which trundling monstrosity they then sneak aboard.
Then somebody's mom makes cookies and the session ends.
Meanwhile in Hollywood I agreed to run a game on-line last Monday.
"So y'all got a choice: take an assignment from the beleagured city of Vornheim, currently besieged by the undead and the goblin lords of Gaxen Kane, or take an assignment from the aforementioned Goblin Lords of Gaxen Kane"
Vote: Goblin Boss job it is.
I was kinda thinking it'd be nice if the on-line people helped save my city--after all, I got books to sell. But no, anyway...Goblin job.
The Goblin King has a grudge from a long time ago.
This goddamned pink-haired war witch and her warband not only humiliated him but reports from the southern frontier indicate they are contriving to discover some kind of mcguffin to save the doomed city.
So, the assignment for the online group: go hexcrawl around and find them.
Now basically, in a sandbox, you have to have about a gazillion half-sketched ideas in every direction and then be prepared to build up on them when the party moves that way. It's a constant back and forth between planning and improvisation and, in the shuffle, some stuff can get lost: the PCs find a problem, half-solve it, have some fun, but then go "Fuck it" and move on 'cause there's D&D in every direction.
The great thing about having the second party chasing the first is that consequences of the party's actions (the engine of typical, structured dramas) suddenly spring up out of everywhere. Things have history and NPCs have allegiances without you even having to try.
So this second party starts looking for the girls: they find the tracks the rolling fortress has left through the jungle. They run into a herd of centigors who kidnap their totally redshirt wizard.
The first party sees this herd of centigors carrying the limp wizard in the next session and has to hide from it.
The second party finds where the rolling fortress clearly ran smack into that lake near Hex 2114 and was attacked by the warband of The Limbless Harlot (like that but, y'know, without the arms and legs). They have to do some forensic work to reconstruct the events.
The first party has abandoned the fortress and made off across the Reach to parts unknown, tangling with and taming an ocelot, and resting with some allied goblins.
The second party likewise makes an impression on some local goblins--the fact that Jez's goblin PC rolled as well as he could on his charisma plus strolled into town riding a man pretty much blew these hicks away--and also a citadel of creepy carrion-crawler god-worshipping serpent cultists who waste no time creepily tattooing party #2 and doubly charging them with the mystical task of finding the troublesome war witch and taking all the magic war witch stuff she probably just looted from the rolling fortress.
The War Witch herself is meanwhile sitting right next to me listening to all this on the laptop and occasionally commenting to Party #2 to the effect that she's noting their various levels and Armor classes. I put it down to prophetic dreams.
And, basically the point is all that thinking you do in a sandbox campaign when you go "Ok, there's a village-- why do they care? What do they want?" between and during sessions is largely done just by GMing the other game. Each party is creating the background action animating the other party's sandbox.
It might sound like a crazy juggling act but in actuality it makes it all much easier--I know exactly what's going on in the whole area all the time because I just GMed it. If I had just written it all out it not only would it've been lonelier but harder to remember.
I suppose if group 2 ever does find group 1 I'll have to schedule a party so they can fight.