David-vs-Goliath tactics

[Felon]

When fighting monsters of large size or greater, players often want to do stuff like jump on its back and stab it, or tumble underneath it and stab its underbelly. They see it in fiction, so they want to try it in the game. Unfortunately, as far as the PHB is concerned, if you enter a monster's square, then you're trying to grapple, bull rush, or overrun it. All of which work heavily against a smaller creatuer.

Is there any support for tactics like this in sourcebooks?

 

[Legildur]

Both Complete Warrior and Races of Stone have tactical feats (and some other relevant feats) that do some of exactly what you are looking for. Additionally, Complete Warrior has a couple of Prestige Classes (eg Gnome Giant Slayer) with that theme.

 

[Felon]

Are the feats in Races of Stone race-specific?

 

[Darklone]

There's the SwarmFighting feat... and some skill tricks that do similar things.

For me, such things have always been flavortext that I used if a PC did something similar in a battle... e.g. tumbled through or around the field of a foe to get into a better position.

 

[Rath the Brown]

Races of the Wild has Underfoot Combat, which is sort of a racial feet in that you have to be Small or smaller. The tactical feet Confound the Big Folk has the same prereq.

The tactical feat Giantbane in Complete Warrior is more open, in that you have to be Medium or smaller.

I couldn't find any feats in Races of Stone that allow to jump/climb onto or duck underneath a larger opponent.

 

[Aust Diamondew]

The real david vs goliath tactic involves staying out of melee range with the big guy and pelting him to death with ranged attacks.

To do some of the things your players want to do just make the options of the tactical feat in complete warrior available to everyone at a penalty.

 

[Legildur]

I couldn't find any feats in Races of Stone that allow to jump/climb onto or duck underneath a larger opponent.

I was looking at the Titan Fighting feat in Races of Stone (Dodge feat as prerequisite). It allows a dwarf or gnome to apply their giant-related racial bonus to AC against their (larger) dodge opponent.

 

[Felon]

To do some of the things your players want to do just make the options of the tactical feat in complete warrior available to everyone at a penalty.

Better yet, I'll let'em spend an action point to emulate the feat.

 

[hong]

What could be interesting is to make the following house rules:

- You can occupy the same square as an enemy creature, if it's larger than you. You take a -4 penalty on attacks and AC, just like being squeezed (which cancels out if you attack the creature whose square you're occupying).

- Size L or larger monsters don't threaten the squares they occupy.

- For more fun, they also lose Dex bonus to AC against opponents in their squares.

 

[Someone]

When fighting monsters of large size or greater, players often want to do stuff like jump on its back and stab it, or tumble underneath it and stab its underbelly. They see it in fiction, so they want to try it in the game. Unfortunately, as far as the PHB is concerned, if you enter a monster's square, then you're trying to grapple, bull rush, or overrun it. All of which work heavily against a smaller creatuer.

Is there any support for tactics like this in sourcebooks?

As mentioned, there's nothing forbidding you or the player to declare they are doing exactly that when they attack normally. It's like declaring they are aiming for the creture's vital points: you are always aiming for the vital points, there's no need to house rule called shots. Or if a rogue armed with a short sword is sneak attacking the monster, it's difficult to picture how can he do it without jumping on his back and stabbing it (cutting tendons becomes repetitive after a while)