We have this situation -and I think it's certainly common-
The group has been ambused in a dark alley. Some roges at ground level, and some snipers at rooftop, weakening the party with their arrows for good measure.
The party cleric points to one of the snipers and casts "COMMAND: Approach" hoping for the sniper to jump down (And receive some AoO while approaching him for good measure, too)
The sniper fails his save, and... well, this is where we are split at the table:
- Should he just walk away 60 feet, to a nearbly staircase and go down, knowing that in the next round he'll be back? Our GM ruled that jumping down would be a suicidal act.
- He must jump down (And try an acrobatics check, or even endure 1d6 damage from the fall) because NOTHING in the spell descriptor says that you cannot issue a command that would result in personal harm
We have a problem with this, because it's organized play.
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PS: It's possible to use some other commands? Like "Laugh" for disabling a caster (You cannot cast anything with a verbal component: You're too busy laughting!) "Applaud" (Like 'Drop' but with some grandiosity) "Swim" (Since you cannot swim in the air, you're likely to act as "Fall", but while waving your arms) or "Dance" (Unless you have some ranks in perform, you look REALLY silly)