My problem with grenades and big explosions ...

[Dana_Jorgensen]

From what I understand, there is a certain distance after which any flying fragments are just too small to be considered lethal. The bigger, more deadly ones won't travel nearly as far.

Past the casualty radius, the fragments are nothing but paint scratchers; too slow to do much more than mar your paint job, chip windows, etc. Sure, they'll cause injury, but penetration is so shallow that you can pick out the fragments with your fingers since they'll still be partially protruding. May as well be bitten by a few dozen mosquitoes instead.

 

[mmadsen]

From what I've read, a modern fragmentation grenade is "100%" lethal within five meters, and causes 50% casualties (death or injury) out to 15 meters.

As others have mentioned, older grenades didn't fragment as effectively, and the concussive blast from a grenade really isn't that bad; I believe an "offensive" (concussion) grenade is only dangerous in a two-meter radius.

If you're in the 5' square where the grenade lands -- i.e., you were the target, and you failed your save -- then you should expect to die from the blast and the fragments.

If you're within nine 5' squares, you should probably roll a Ref save for each die of fragmentation damage -- so they might all miss you, or they might all hit you, but you'll probably take a few hits.

Of course, this is hard to reconcile with massive hit points.