Is there a type of thrown object that can do damage, cause distractions, cover advances, start fires etc? I am basically looking for a medieval grenade. I think I saw something in one of the books, but all I remember is that it involved alchemy and am pretty sure the group of items are called alchemist grenades. My searches thus far have yielded nothing but home-brews. Can anyone find the book it is in please?
Splash Weapons are found in many books, including core
Splash weapons work like grenades: they are thrown, and they cause some effect in an area, or to whoever was hit plus others in an area around that person.
The core splash weapons are:
- Acid – deals acid damage
- Alchemist’s fire – deals fire damage
- Holy water – hurts undead and evil outsiders
- Tanglefoot bag – entangles creatures
- Thunderstone – deafens creatures
Many books added more of these. Most are, sadly, overly expensive for their effect, and difficult to use. Many offer very-low save DCs to halve or negate their effects, which makes them fairly unreliable, as well.
Oriental Adventures actually used the word “grenade” for its eggshell grenades. These are splash weapons created by filling eggshells with some unstable substance. They also turn out to be some of the most effective splash weapons printed for 3.5, particularly the dust one which blinds the primary target for 1d4 rounds with no save.1
- Secondary targets get to save, it’s not a hard save, and even if they fail it’s only 1 round for them, so this is most useful for just blinding that one guy you need blind. But for that purpose, they are amazing. So good you might get them banned if you over-use them.
Like everyone else said, there are various thrown splash weapons.
I could stop here, but I have a different prediction.
This is a Pathfinder class, not a 3.5 one, but it might be what you saw. The two systems are very similar.
The Alchemist uses 3 special abilities: extracts (basically spells); mutagens/cognatogens (increasing a physical trait at the cost of a mental one or vice versa); and most importantly for the question, Bombs. They do a number of d6 damage related to your alchemist level. It may not be what you're talking about, but alchemist's grenades sound too much like this class's bombs to me.
Alchemist's Fire is a thrown weapon that does splash damage to all enemies surrounding the target. It's sort of like an alchemical Molotov Cocktail that causes the target to burst into flames. While it's not quite a grenade, it has effects similar to what you're looking for.
The fire it starts only lasts for 1 round, and it doesn't have RAW rules for starting fires or distracting enemies. However, a large fiery explosion from throwing the Alchemist's Fire should act as a firestarter and do everything else you said, but your DM would have to make the call. Assuming they don't play entirely by RAW, it'll do everything you need.
If your DM allows stuff from other settings...
Eberron Campaign Setting has "Acidic Fire" (p. 120) which is the best of alchemist's fire and acid combined into one. 1d4 damage unless it's vulnerable to fire or acid or both.
If you're fighting undead or light-sensitive monsters, look for "Alchemical Sun Flash" in Expedition to Castle Ravenloft -- it's alchemists' fire plus bright light.
Dragon Compendium has the Firestone - 1d6 damage.
And how about a regular net?
These and other splash weapons are in "Shax's Indispensible Haversack" on another forum.