You've got three sessions, two hours apiece. There are seven players. None of them have used the virtual tabletop you use to run games. There are bound to be discord problems, Foundry problems, and more. How do you get it all done in three sessions without boring the players?
In my experience, D&D sessions go like this:
Session is scheduled for 6pm-8pm.
That structure is pretty consistent - players are going to show up a bit late, the game will start a bit late. This is normal stuff, but when you're on a tight schedule with a small budget of sessions, you need to plan for it. Because in a one-shot/two-shot/three-shot type of game...
Seriously, everything. I managed to get my players through the last session only by cutting things out. The final boss, a resurrected, undead dragon zombie pieced together from multiple sources of dragon parts? Cut. The chase sequence where the players had to flee from a horde of bloodthirsty goblins? Cut. An entire session's worth of quest? Cut.
All exposition, all enemies, all skill checks, all combat, it's all optional. I like to treat D&D like a social experience; the main goal is to interact with other people in a fun, meaningful way. Sure, hitting zombies with swords is fun, but even if all we do is talk for two hours, that doesn't mean the session wasn't a success. A session is only a failure when people don't have fun.
When you're on a budget, you want to make sure to prepare less than you think players will finish. I talked a lot about cutting stuff, but it's easier to pad out the time you have with good old fashioned roleplaying than it is to remove a delicate piece of a carefully crafted narrative. Keep the plot points simple, easy to communicate, and something you can expand upon... or not, if you run out of time. The entire plot for my three session, seven player whirlwind:
And that's it. The fully expanded version that I ended up with looked like:
That structure could have been expanded or could have been shrunk. If I hadn't gotten all the way through the goblin cave rescue, maybe the necromancer would have been there in the cave instead of underneath a crypt. There are so many ways to fit things into the time you have. Always be adjusting, reacting, and adapting.
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