Looks: A small black woodden or metal ball that is filled with gun powder and razor sharp dragons teeth depending on the teeth is the effect of the bomb. (it explodes on contact to any target )
Velocilprey fang wider area of effect and makes the explosion equal to a large barrel bomb.
Genprey fang chance of paralisis
Ioprey fang chance poison
And of course the normal grenade has normal wyvern teeth that shred the target and at the same time acts. As a concusion force like blunt force trama enough to equel a small barrel bomb.