Joining us in the blue corner, are those stalwart adventurers from G1! Let's hear it for the G1 characters! Yay!
Frush O'Suggil. Human Fighter 14. HP 104 (Con 17)
Redmod Dumple. Dwarf Fighter 9. HP 82 (Con 17)
Beek Gwenders of Croodle. Half-Elf Ranger 9. HP 93 (Con 18)
Joining us in the red corner, are a few creatures from the Monster Manual! Hiss! Grr!
Aerial Servant - max 32 damage (HD 16)
Baluchitherium - max 40 damage (HD 14)
Cave Bear - max 28 damage (HD 6+6)
Stag Beetle - max 36 damage (HD 7)
Bulette - max 84 damage (HD 9)... and Redmod Dumple is down!
Carrion Crawler - max 0 damage. (go figure)
Chimera - max 34 damage
Type VI Demon - max 54 damage
Pit Fiend - max 20 damage. (Wimp!)
Tyrannosaurus Rex - max 52 damage
Dragonne - max 34 damage
Dragon Turtle - max 56 damage
Earth Elemental - max 34 damage
Loxodont (African Elephant) - max 68 damage (huh?)
Ettin - max 34 damage
Cloud Giant - max 36 damage
Fire Giant - max 30 damage
Storm Giant - max 42 damage
Iron Golem - max 40 damage
Hydra - max 40 damage (12-headed hydra, but only 4 can attack one opponent)
Kobold - 4 damage
Lynx, Giant - 8 (
"Whaddya mean we gotta talk to this lynx?? The last mnster we talked to ate half the party!")
Manticore - 36 damage (spikes)
Mastodon - 68 damage (the moral of the story is: don't anger the elephants)
Nightmare - 28 damage
Nymph - see below (a double entendre!)
Ogre - 10 damage
Giant Otter - 18 damage. (Yes, a giant otter is more dangerous than an ogre. Huh?)
Owlbear - 24 damage. (New Owlbear in Blood War. Yay!)
Piercer - 24 damage.
Purple Worm - 32 damage (and hope it doesn't roll high!)
Remorhaz - 36 damage
Roc - 36 damage (Despite the roc carrying an elephant, I'd still prefer to be attacked by the roc.)
Sea Lion - 24 damage
Shambling Mound - 32 damage.
Shrieker - nil. (Its friends, on the other hand...)
Criosphinx - 34 damage
Su-monster - 24 damage (I still don't know what one is)
Titan - 90 damage (17+ HD) ... and Redmod Dumple is down! But Beek is still going!
Troll - 28 damage
Umber Hulk - 34 damage
Whale - 60 damage
Xorn - 33 damage
The Adventurers win!
Now, obviously I've left out the unique creatures and dragons. I've also used some rather High-Con PCs.

I rather doubt any fighter of less than 15 Con is going to reach 10th level. 15 Con says "I have 62 hit points at level 10 on average." 16 Con gives 71 hp.
Cheers!