Alright, so I'm going to throw out some examples of GM Force, all using the same ruleset; 5e D&D (as everyone here is at least passingly familiar with it).
I'm going to start with (imo), the best part of the ruleset; The Social Interaction conflict mechanics.
I'm going to use a Ranger trying to entreat a domesticated, traumatized, starving, old dog to come back with her to camp where she hopes to use Speak With Animals to communicate with the creature in the morning (to learn about a situation that the dog witnessed);
@Nagol . In this case, the GM just doesn't want this dog to be befriended because they want to keep the mystery of the situation in play for awhile longer. They're enacting a classic "Block" against a gather information/divination player move.
- While this dog is in bad shape, it isn't feral. Its domesticated.
- The dog was saved by the PCs from certain death and then ran off into the night when things got dangerous. This is a dog; it knows the PCs helped it.
The players are
expecting the creature's Starting Attitude to be Friendly because of the above (as most dogs start friendly to strangers even without the stranger aiding them!).
1) The Ranger successfully tracks down the dog due to Natural Explorer and a high Survival Check so this can't possibly be blocked (or the Force will be so overt that it will cause a problem at the table).
2) Through a series of canine-esque social exchanges, the GM tells the Ranger player that the starving dog is fixated on its pouch where she keeps her dried jerky. This is a cinch. The Ranger player bends down, opens the pouch while reaching in and eyes the dog carefully (makes an Animal Handling check to uncover the I/B/F related to the food). The Ranger gets a 12 on the AH check. The player figures its got to be good enough to uncover the I/B/F and that the dog just wants some food. The GM says the dog just looks on warily, making no move to come forth (confirming nothing and not moving the social engagement forward).
The Ranger player is incredulous. How can a 12 not do the trick here? They were expecting success and to be able to deploy the I/B/F for advantage in the coming Charisma check or to increase the Attitude one level before the Charisma check.
3) A blizzard is coming in, its a freezing night, and predators lurk on the tundra. This is going nowhere and its getting dangerous (with the risk of the Exhaustion Track coming in play).
The Ranger player says, "enough of this, I open my pouch, brandish the jerky and move forward to the dog to give it to it manually." This forces the Charisma check to determine the dog's reaction.
The GM then says that the dog flattens its ears and growls as the Ranger approaches. Again, the player is incredulous. "Wait, what? This dog is Hostile? How?"
The GM explains his case for a Hostile Starting Attitude (starving, trauma, and the dog appears extremely paranoid by the Ranger...maybe something in its recent past).
The Ranger player is incredulous. Even if they buy the Starting Attitude of Hostile, it should have been moved to Indifferent from the prior actions of saving the dog...but...sure.
A Charisma check is virtually pointless here as the Ranger would need a 20 in order to get it.
4) Alright,
Animal Friendship it is!
GM rolls in secret behind the screen and gets only a 2, but comes back with "the dog furrows its brow and emits a low growl; its clearly not ensorcelled".
In reality:
The GM made 3 separate moves of Force to enact this block (fudged Animal Handling DC > adversarial, but skillfully justified, Starting Attitude shuts down Charisma check > fudged Wisdom Saving Throw.