One hole in the rules that my players helped me find was a blind spot on how to handle grenades. Here is my proposal.
Throw them as a challenge test, and if there’s a way they could cause problems, a challenge/risk test. The GM and player agree on the intent, possible consequences (good and bad), what kind of roll before the player rolls–there should be no surprises.
On a success, the grenade lands where the thrower wants it to and targets take expected damage. If the roll does not succeed, then half the targets take half expected damage. If the roll fails, then the GM can predict that the bad bounce could do full damage to allies, or bring down the ceiling, or bounce off and do no damage to anyone. If there are various possibilities for a bad bounce, the GM can even list a number of possibilities and be prepared to randomize between them (like a behavior chart for the grenade.)
This should not bog down the game speed. The player declares intent, ideally looking at a visual representation of the area. The GM agrees with how many targets could be hit by a good throw, and sketches out a couple other possibilities in case of failure. The player rolls, adjusting the roll with Resolve if desired. Damage is worked out, and the game goes on.
Athlete skill can be applied to the roll, and Support characters get a secondary skill equivalent for throwing weapons in combat.
Most hand-held explosives have a thrown range of about 30 feet with any accuracy. They explode for full damage with a 10 foot diameter and half damage for another 10 foot radius beyond that. Specific mixes may vary, but that is the baseline.
Firebombs do 1d6 x 2 damage for one round, and 1d6 damage the next round. That’s for alcohol or oil; napalm style flames may do 1d6 x 4 at one less multiplier a round.
Standard gunpowder bombs rely on placement, so use the thrower’s ranged weapon damage code x4 in the 10 foot diameter, and x2 in the 10 radius beyond that.
I’ll also work something up for web bombs, smoke bombs, flash bombs, and such. Making these bombs will be the domain of the alchemist, and gunsmiths can make gunpowder bombs.
What do you think?