Yesterday I played my first game of AH. A question came up regarding monster damage. We were two players vs. Yig. How exactly does the final beast take damage? It’s worded funny. I figured that it went like this: each player rolls all their attack dice, records their total number of successes and it’s divided by the two players to arrive at the number of hit point damage. For example if I rolled three successes, and my other player rolls one, a total of four successes are scored and this divided by the two players come to a total of two hits of damage. He thought that no matter how many successes we scored, as long as we had at least two successes we get one hit. This made rolling his attack redundant if I get at lease two successes, and that we could only ever score one hit at a time. Also, looking at Cthulhu himself…he regenerates one hit of damage every turn/round…so it would be impossible to take him out (same as some of the others). Then he suggested that perhaps we each roll for hits and apply up to one  hit of damage each. This didn’t make sense either, because if you were playing with up to five players, each has to get five successes to do one point of damage (impossible in some situations, or for some players). It also conflicted with the way the rule was written, stating that all players total their successes and then apply damage.
So, my question is…do all players total their successes, divide by the number of players and then apply that amount of damage to the monster (be it one, two, or two hundred points of damage) and discard/reset the number to zero before the next round of combat (after dealing with it’s attacks, etc)?

As the BGG guy noted, it's nothing more complicated than (investigators) x (doom tokens).

Yog-Sothoth starts with 12 doom tokens. In a 3-investigator game (even if some were devoured at start-of-battle), it will take 36 accumulated attack successes to win.

The only oddity is with Cthulhu, who heals back a single doom token after he attacks, as long as he's not already at 13. This would mean that in a 3-investigator battle, he "heals back 3 successes" after each of his attacks.

Hope that helped!

 That’s a whole lot more damage points than I first envisioned. I don’t remember reading anything about multiplying the doom tokens by the number of investigators, but I do remember that it says to “total all the players successes, and for every amount that it equals the players, one point of damage (doom tokens) is removed. The numbers are then reset after the end of that round of combat.”

LynchMob said:

Rules for Final Battle are really horribly worded. Tibs is right, every doom token to be removed requires N successes, where N is the number of investigators. You keep tally of the successes, so if you're fighting Yog with a four investigator team, you need 48 successes. If after the investigators attack phase Yog has 31 "hits", after his attack is resolved, you still need 31 more hits to win the battle.

LynchMob said:

Almost right except that you don't reset excessive successes after each combat round. If you score a total of 8 successes in a 3 player game you remove 2 doom tokens and the 2 extra successes are carried over to the next round.

So as Tibs said, each ancient one requires exactly (number of doom tokens)x(number of players) successes to be defeated.

Tbla said:

Good to know, that answers the question I came to the board for :-)