So, the situation is that I run games for a group of up to 8 players. Of them, 5 are regular weekly players and 3 are occasional, every month or two players due to work shifts and geography.

I've been playing with these guys for years now so I don't want to exclude anyone.

How should I handle obligation? If I give starting obligation of 5, that would be way to low for regular sessions. If I put it at 10, that would be excessive for the few sessions every now and then when my table is full.

Should I only roll against obligation for those PC's in attendance (kinda breaks the 4th wall for me)? How would my fellow GM's handle this situation and this mechanic?

Character creation and starting obligation should be 5 as per the rules as you have a total of 8 players. Then see how many of them buy XP or credits at character creation and add it all up.

As you suggested, just count the obligation of those players that have actually turned up. After all an Obligation trigger is meant to only last that session and is based on the players character that the roll has come up for.

I have a similar situation. I had about 8 players initially express interest. An actual 6 have followed through and created characters with Obligation 5, and 2 of them took on additional. At most, I had a group of 8, with 2 players running pregenerated characters, and one standing in for a regular who couldn't make it. Most sessions, however, end up having 5 or 6 players.

We're not on a regular gaming schedule, because we all have changing schedules in real life. I usually make the Obligation Roll while preparing for a session so that I can plan for a more narrative complication as opposed to just lowering the Strain Threshold. The problem is, what happens if the player whose obligation was triggered doesn't show up? I'll re-roll for that session, and "bank" the triggered Obligation for the next time that player is in.

I've got the same type of group myself. Each of us take turns GMing various games. We unfortunately don't have a dedicated GM or one who likes to GM. And to throw in an extra kink, my girlfriend and I are playing AoR characters. lol But, I'm thinking about looking for another group to play more often with. A set of brothers spend 100s of dollars on RPG related tools, Dwarven Forge, Generic GM screens, wet erase mats, dry erase boards, more Dwarven Forge sets, and all of them are bored or RPGs, yet, they're spending tons of money on the X-Wing game. Argh!

wow, i am overwhelmed with 5-6 players.

hats off to you

i would be trying to figure out a way to streamline obligation a bit, perhaps by grouping up characters with "shared" obligations

In your situation, I would just use the 5 base Obligation per player since some of them might Double Down. Build the Obligation using all of the characters, but when you roll it, only the characters whose players are present for the session count. Players who aren't there that week have their character's Obligation count as a non-result.

I would NOT "bank" their Obligation roll results since that would lead to them facing their Obligations a much higher percentage of their game sessions than the weekly players. They're there to have fun, not get dumped on every single time they manage to be able to show up (having your Strain Threshold take the big hit, having your drama come up AND being behind the weekly players in XP (and thereby character ability) is a triple whammy).

I would NOT "bank" their Obligation roll results since that would lead to them facing their Obligations a much higher percentage of their game sessions than the weekly players. They're there to have fun, not get dumped on every single time they manage to be able to show up (having your Strain Threshold take the big hit, having your drama come up AND being behind the weekly players in XP (and thereby character ability) is a triple whammy).

Hmm, good point. I hadn't thought of it that way. It hasn't actually happened in my group yet, and I can safely write it off as a bad idea. (sometimes ideas sound better coming up with them than trying to put them into practice.)

Washer: my record was 16 players in a DnD 2nd ed game. But that was years ago. The old brain was strained running for 8.

I have gone for the 10 obligation each, but only rolling against the obligation of players who are at the session. Seems to be working so far.

I've got an almost identical situation. I went with base 5, and plan to roll against only those present. However, Obligation they acquire during gameplay may end up being "shared" Obligation, which would not belong to any particular character but to the group as a whole.

For example, one character may take on Debt mid-game to finance some endeavour, but if the whole group steals a starship, that Criminal will belong to the group, rather than individuals. When triggered, everyone would reduce their Strain Threshhold by 2.