POLLY WANT A BIG CRACKER!!
While running my Barrowmaze campaign a while back, the party stumbled upon a small Roc as a random wilderness encounter. No combat ensued (hooray for non-hostile reaction rolls), but it did mean taking a good look at its stats. I commented on how interesting the beasts were as written and one of my players suggested that an RMA might be in order. So here it is.
Roc, S/M/L (from Cook)
Move: 60' (20'), Fly 480' (160')
Att: 2 claws/1 bite
Dmg: 2-5, 2-5, 2-12/1-8, 1-8, 2-20/3-18, 3-18, 8-48
No. App: 0 (1d12)/ 0 (1d8)/ 0 (1)
One omission in the Cook Expert entry is the Save As listing (typo).
This one took a little research because despite the fact that the entry includes three different sizes, the descriptive text is pretty sparse. I cobbled together a mental picture of ol' Beaky between BX, LL, 1st ed. AD&D, and d20 (3e).
One thing to keep in mind is that these are some truly formidable birds. Even the small one is no picnic considering there might be TWELVE of them flapping about. At 6HD minimum, Sleep spells are useless, too. The AC not great for the smaller ones, but it's not terrible either. Three attacks at middling damage can mean a bad day for someone who looks like bird food. Small Rocs are relatively skittish though, so you might scare them off.
Medium Rocs are significantly tougher (x2 HD than small) but otherwise similar. Their bite is impressive though.
The Large Rocs are crazy! More HD than a Dragon Turtle! AC 0! Attacking with both claws and beak can deal up to eighty-four points of damage per round! Despite their hugeness, rocs' flight speed (all three sizes) is unbeaten and nearly unmatched.
I assume that the sizes are age categories and all rocs eventually become large ones (if they reach full maturity).
The alignment is worth noting. It is a lawful creature that reacts poorly to neutrals and chaotics. They are not particularly intelligent, though. It makes me wonder how they make distinctions with whom they are dealing.
They have a fair chance of treasure lying about the nest (mostly coins and jewels per the chart), but the real wealth would be to make off with some of the eggs. Such chicks can be trained as mounts, which should entice some PCs to risk tracking down a roc eyrie. The 1st edition AD&D Monster Manual has a fun note, too:
"Rocs are occasionally tamed and used by giants."
At first, I thought they meant as hunting birds, but no. According to the Storm Giant entry, they RIDE them! Imagine that encounter! A couple of giants flying at you on the back of a bird that can pick up an elephant!