One of my few complaints about AH in terms of the design/gameplay is that investigators cannot gang-up on monsters. I think in thematic terms and in the sense of adding more co-op interaction among the players and the characters, it would be better that way. But for whatever reasons (and they may have been very good reasons), the game wasn't designed that way, and as it is, the system would not work if more than one investigator could fight the same monster... it would be way too easy to clean them all up. But I'd like to discuss some possibilities for adding that to the game, and what would need to be adjusted to balance that, and I'm looking to test some possible solutions.

My initial thought is that you could keep the turn order, so for example Inv1 moves to a 3 toughness monster and attacks it, doing 1 damage (put a Stamina token on the monster), then Inv2 moves there and finishes it off, scoring the other 2 hits. The question is, does Inv1 incur some damage as a result of not finishing it off? If the monster is not killed, does it heal its damage by 1 toughness per turn? Is there some adjustment needed to the combat rules in that case?

Another thought is to add a phase between Movement and Arkham Encounters; the Combat Phase. Any investigators who have moved to a location with a monster will fight them during that phase, which may include more than one investigator fighting the same monster(s). So in that case, it would be more of a simultaneous thing. How to adjust then, so it's not too easy? Of course, the thing is, it should be easier to kill a monster with more than one investigator fighting it... that's the whole point. But not to the extent where it becomes a cakewalk or totally unbalances the game. And in that case, which investigator gets the monster trophy? I'm guessing they could choose who needs it more...

I suppose, though, that merely taking a turn and movement for an extra investigator or two to focus on a monster takes away from their focus on other things, so I don't want to go overboard in terms of compensating for it being easier to kill monsters. But inasmuch as monsters will certainly be easier to polish off and monster trophies easier to come by and spend, then something would need to be done. Perhaps the simplest adjustment might be to just lower the monster limit by 1 or 2 and the Outskirts limit by 1 or 2. I'm not sure if that's quite enough, though.

So how to have multiple investigators attack a monster without needing to change any of the card/board stats or abilities in the game, with only a minimal mechanic addition or adjustment... that to me is the goal here. Question is... can it be done?

One of my few complaints about AH in terms of the design/gameplay is that investigators cannot gang-up on monsters. I think in thematic terms and in the sense of adding more co-op interaction among the players and the characters, it would be better that way. But for whatever reasons (and they may have been very good reasons), the game wasn't designed that way, and as it is, the system would not work if more than one investigator could fight the same monster... it would be way too easy to clean them all up. But I'd like to discuss some possibilities for adding that to the game, and what would need to be adjusted to balance that, and I'm looking to test some possible solutions.

My initial thought is that you could keep the turn order, so for example Inv1 moves to a 3 toughness monster and attacks it, doing 1 damage (put a Stamina token on the monster), then Inv2 moves there and finishes it off, scoring the other 2 hits. The question is, does Inv1 incur some damage as a result of not finishing it off? If the monster is not killed, does it heal its damage by 1 toughness per turn? Is there some adjustment needed to the combat rules in that case?

Another thought is to add a phase between Movement and Arkham Encounters; the Combat Phase. Any investigators who have moved to a location with a monster will fight them during that phase, which may include more than one investigator fighting the same monster(s). So in that case, it would be more of a simultaneous thing. How to adjust then, so it's not too easy? Of course, the thing is, it should be easier to kill a monster with more than one investigator fighting it... that's the whole point. But not to the extent where it becomes a cakewalk or totally unbalances the game. And in that case, which investigator gets the monster trophy? I'm guessing they could choose who needs it more...

More cooportation/conflict! Actually I tried this for a while. It just didn't come up very often and wasn't worth the effort of explaining.

I suppose, though, that merely taking a turn and movement for an extra investigator or two to focus on a monster takes away from their focus on other things, so I don't want to go overboard in terms of compensating for it being easier to kill monsters.

That is a major downside. Does an investigator use up a turn in such a situation to help another perhaps unneccesarily? Turns are really very precious.

But inasmuch as monsters will certainly be easier to polish off and monster trophies easier to come by and spend, then something would need to be done. Perhaps the simplest adjustment might be to just lower the monster limit by 1 or 2 and the Outskirts limit by 1 or 2. I'm not sure if that's quite enough, though.

You need to allow the monsters to gang up on the investigators too then! No taking the monsters on in the order of the investigator's choice while the other monsters patiently wait to (usually) be slaugtered or the investigator mysteriously disappears from sight and smell. Now they all hit and now the investigator can only attack one of the monsters. Or to keep more with current (inexplicable) rule where the investigator almost always gets first attack, all surving monsters than strike back. You'd need to figure out a way to determine again which investigator they attack in a complicated combat. I'd probably give the investigator an Evade check against each other monster.

So how to have multiple investigators attack a monster without needing to change any of the card/board stats or abilities in the game, with only a minimal mechanic addition or adjustment... that to me is the goal here. Question is... can it be done?

I think it can be done rather easily. I'm not sure its really worth it.

In the old forums, 357magnum proposed a house rule for teaming up on monsters. The original post doesn't exist anymore, but this is more or less what he said

Mythos phase: A Gug appears in Uptown streets.

Michael McGlen (current Fight 3 + Tommy gun) is already there, so he's supposed to evade or fight it during his turn. Richard Wilson (current Fight of 1 + Shotgun) joins the fight before Michael's turn.

The players choose which investigator will roll. If Michael rolls, he can add +1 (Richard's Fight) to his check. If Richard rolls, he can add +3 (Michael's fight) to his check.

The players decide to have Richard roll. Both Richard and Michael make the horror check. If Michael goes insane, Richard won't be able to use Michael's help in combat. Both investigators pass their horror checks. Richard rolls but doesn't get enough successes. Therefore, both investigators suffer the Gug's damage! Next round, Richard manages to splatter the Gug's a*s all over the neighborhood. He can claim it as a trophy. Helpers never claim trophies.

So, as you can see, this rule doesn't break the game much: it's not very useful as the helping investigator has to spend his whole turn on a monster, taking all the risks involved and without getting any trophy. Still, this rule helps.

Also, there's no limit to the number of investigators who can help. Both Mark Harrigan and Joe Diamond could help Michael McGlen against the Dunwich Horror! You could say this makes the fight a lot easier, since the Fight value is not modified by resistances or immunities, but this is compensated by the investigators (as a whole team) wasting too much time and manpower.
For example, in a 4 player game, if 3 investigators fight the Dunwich Horror this way, the game would likely get a bit out of control: a new gate, more monsters around, etc.

We also decided that anyone cooperating in this way also ends his movement there, unless you're a... One Man Army [meaning Mark of course - avec]

i don't like some mechanics of this suggestion. how about:

1. move all combat to the end of the movement phase for all players simultaneous, or include a combat phase between movement and encounter. (note: this makes the game harder because it is no longer possible to clear a street for another investigator who moves later). of course if a combat occurs during encounter phase it is resolved instantly (as per the rules), of course if multiple investigators are at that location they fight together.

2. if an investigator fails an evade check (while trying to sneak past a monster) he takes combat damage once and may not move anymore.

3. during combat phase, all investigators, who are in the same area as one or more monsters, must fight them (again this may make it harder because in the original rules only the first player entering the area had to fight including the horror check, provided that he is victorious; and players moving later already knew how the fight ended).

4. fight works as follows:
a) all investigators make the horror check.
b) investigators choose the order of combatants. one investigator is the first fighter, next one the second fighter and so on.
c) do all things that happen at start of a combat round (equip items etc.)
d) all fighters make the combat check and add their successes together. however, the 2nd fighter may only roll half of his dice, the third fighter only a third of his dice etc. divisions are made AFTER applying all modifiers. round fractions mathematically (0.5 rounds up, below 0.5 rounds down).

example: monster has modifier -1, physical resistance; 2nd fighter has fight 4, and a shotgun (+4 but physical weapon so it gets halfed). he rolls 3 dice (4+2-1)/2 = 5/2 = 3

e) if the monsters is killed (at least as many successes as toughness), the first fighter gets the trophy. if the monster is not killed, all investigators take combat damage and another combat round starts (damage on monster is reset as usual). repeat b)-e) until all investigators (or the monster) are (is) dead.

so, looking at this, what does it do? makes it harder to move around in arkham because monsters are not killed until all investigators are moved. investigators that are caught sneaking and survive the first damage, may be rescued by other investigators (this is what i like the most). investigators may help each other in combat, though each additional investigator faces the sames risk and contributes less. i think this is balanced. it might encourage people to use higher sneak and will values more often than i usually see in our games.

I agree that the thing I like most about it is the ability to rescue someone who failed a Sneak check and is likely to be doomed in combat... and yes, you may prevent them from being knocked unconscious but they still took a nasty hit for it. I also like this for the situation that comes up once in a while where a certain nasty yellow-bordered monster (physical/magical immunity, 3 toughness, etc.) gets in the way somewhere and it seems to take a ridiculous amount of time to do anything about it. This would require some coordination and effort, and as we've mentioned before it's always going to be questionable whether using your valuable turn to gang up on a monster is really worth it.

I do like the system letsdance describes and I'm going to try that out sometime soon... Asking people to divide by 3 isn't always a good idea, but I think that would be pretty rare to have more than 2 investigators ganging up on a monster.

Another thought I had is to keep the phases as they are, and have it work where investigators who join a fight get negative modifiers based on the number of investigators there and the number of "wounds" the monster has... implying that the monster becomes more desperate and dangerous when it's wounded and when more people are attacking it. So for example, Inv1 goes in to fight a 3 toughness monster and does 1 damage. Inv1 then "flees", but one wound marker is added to the monster and Inv1 remains in the location. Inv2 goes in but has a -3 modifier (in addition to whatever the normal modifier would be); -2 because there are 2 investigators there and -1 because of the wound the monster has. Inv2 does 1 wound but is knocked unconscious and is moved to the hospital. Inv3 moves in, but will have a -4 modifier... 2 investigators are there + 2 wounds. It would have a similar effect as letsdance's system but would keep the turn phases intact as they are. One question would be whether an investigator who happens to be there but successfully evaded that monster to begin with should count as a negative modifier if 2 or more others want to fight that monster. I would say yes at the point when the second investigator begins their attack, just to keep it consistent (it sort of works like Small World's method of counting a region's defense by counting the number of pieces there). And whichever investigator finishes the monster off gets the trophy.