Has anyone tried this? "Colossus" monsters

[Amastacia_Seijin]

I'll be playtesting it soon(ish) and was wondering if there's any past experience I should know about.

The idea is very heavily inspired by Shadow of the Colossus. Basically, in order to have a fighting chance against the BBEM, you're going to have to climb up it.

I won't be using glowing runes as weak spots, although, in a moment of cruelty, I've decided that the monster used has a base creature type of a hawk-- In other words, they're fighting a flyer.

It's 35 feet long (40 if you count the beak), and has a 70 foot wingspan. There's a 3x3 area that makes up the back, and the party can stand there with no climb checks if the bird is flying level. It can, of course, fly sideways in a turn (+5 to climb DC) or even try to shake the party off (+10 DC). Standing on the head or tail is more difficult (DC 5), being on the wings is extremely difficult (DC 20), and being on the talons is fairly easy (DC 5). Trying to hang from the underside adds 10 DC to these checks.

Now for the kicker to explain the low DCs for a high level fight: When the party made their characters, they didn't know they would be doing this.

The hawk-ish creature is mostly composed of pure magical energy, which will randomly (1d4 rounds) discharge. Anyone standing on one of those squares gets hit with 10d6 damage, reflex save of 23 for half damage. Attacking these areas physically does no damage, but it's very vunerable to magical effects. For example, dispel magic does con damage that will last at least the rest of the fight, and being in an antimagic field does near-lethal or lethal con damage (15d3, it has 36 con)-- Leaving the field heals that damage, though.

A small part of the body is still fleshy featherstuffs. Attacking this is subject to a rather nasty 20/epic damage reduction. Otherwise, it's rather boring.

About the same amount of area is composed of vellum and paper. These are the weak spots, the glowing rune equivalent, although these attacks at best are meant to just guarantee a death through con damage. Attacking one of these areas ignores that terrible damage reduction.

Two unique rules apply while climbing on the monster. First, a character may take a full-round action to take 20 on a climb check. This is to make up for the fact that most of the group has 0 ranks in it. Second, touch attacks automatically succeed both ways. This is most important because not only does the party have multiple spellcasters, but the creature is a spellcaster, itself.

Finally, to force the group to take to the idea of climbing the monster, it attacks while they're on a boat, and, well, it literally attacks the boat.

So anyway, does anyone have any feedback on SotC-style DnD? If this campaign goes well, I'd like to do more of them. To me, it's hard to get more epic than fighting something so big, you have to climb on it just to hurt it.

[Darkshade]

what if the PCs can fly?

[Amastacia_Seijin]

Then they fly, and the monster is now capable of physically attacking them-- Which, mind you, is a pretty nasty attack.