I discussed this a bit with Alex (of Cirsova): how to make giants or colossal monsters functional differently that big, fat bags of hit points.

I’d like a system that works just as well for monsters that are 30-50 feet tall (and also ‘long’ monsters like hydras and titanic snakes) as those creatures whose height is in excess of 100 feet.

Games like Shadow of the Colossus, God of War, and Dragon’s Dogma have you climbing atop giant enemies to stab at their vulnerable parts. Climbing the Colossi is most of the apparent gameplay in SotC, and many of GoW’s most cinematic battles are its puzzle-boss fights.

Dragon’s Dogma enables a level of “grappling” that I haven’t seen in many games (with Assassin’s Creed being a possible exception) — allowing you to scoop up friends or foes, or cling to giants, chimeras, hydras, and dragons.

Sure, you don’t have to scurry up the cyclops and stab it in the eye… but who wouldn’t want to scurry up the cyclops and stab it in the eye?

Maybe it’s because I’ve been experimenting with 1e’s Appendix A but I was able to imagine a giant as a series of vertical passages and rooms. It might seem silly but I think somewhere down this line of thinking lies an answer.

First, let’s think of a 30′ giant — just standing there, we’ll get to movement later. Two arms, two legs, a torso, and a head. We have a vertical dungeon instead of a horizontal one, with each limb a passage connecting to its torso.

We don’t want to make the fight tedious, so we’re going to wave “climb” checks for the time being and assume that any character can scale a giant at about half their normal speed. What are your basic hazards?

The biggest one is falling. (Or being thrown.) But let’s back up.

The main “points of entry” in this dungeon are going to be whatever parts you can reach — that’s usually going to be the giant’s legs and feet, which are going to be the equivalent of various crush-or-slam traps.

When you initially try to scale a giant you have to worry about getting stepped on or kicked. This could be handled with Reflex saves and Readied actions.

Another possibility would be grabbing the giant’s arms while it was trying to squash you or swat you away. This gets you closer to the head faster — but it has the potential to get you to ‘dead’ faster. Readied actions and Reflex saves.

Once you’re climbing, I wouldn’t have players check to hold on except under two circumstances — when they moved between limbs, or when the giant took action to remove them. (Grabbing, slapping, rolling on the ground, etc.)

3e has rules for “attached” creatures like the stirge or dire weasel — and the rules for them bear a resemblance to the climbing rules. Climbing creatures are denied their Dexterity bonus to defense, particularly their AC.

Scaling a creature seems similar to climbing, or ‘attaching’ to them.

So, what about hit points?

I think The Angry GM makes a good point about multistage boss fights with walled-off hit points in “Return of the Son of the D&D Boss Fight.” It seems like giving each of a giant’s limbs its own “bag of hit points” would be a great way to stage the battle. Instead of killing the giant, you hurt it until it flees.

Now, there’s a whole range of places to go with this — how crippling/killing different parts of the giant will affect the whole, but that’s going to require the codification of a few basic concepts, like “how do you even get up there?”

More on this later.