T-rex charges in 1st round, gobbles up a player …
The tyrannosaurus couldn't possibly swallow anyone until the second round.
And as luck would have it, the fighter had no light weapon.
No dagger, no spiked gauntlets, no armor spikes, no
arrows?
Expedition to Castle Ravenloft has stats for ipecac. Each dose costs 5 gp and induces immediate vomiting and 1d4 rounds of
nausea with no save against either effect. It's normally not effective for offense because of the difficulty of getting it into an enemy's stomach, but if you're already there, you can just dump it out.