I was summoned as part of the forest covenant.  After the usual bowing gestures, me and the host face off, only to see the note that another invader had arrived.  Not paying too much attention, I keep fighting.  Suddenly I see tranquil walk of peace being casted off screen, which hits both me and the host.  The person that casted it was not another forest invader, but a darkwraith.  Since both me and the host were slowed, I just started spamming wrath of the gods which killed both him and the dark wraith.
 
Ok, so maybe that's not really coexistence, but the game does allow for 3 way free for alls it seems.
 
Now, the quesiton is can we have someone being invaded by forest invaders, blades of the dark moon, and darkwraiths while having a white phantom and warrior of the sun on his side?  And perhaps they can just line up and do a merry jig instead of fighting and post it on youtube?  Pretty please?

@Turambar: I am a forest hunter, got summoned and found the host fighting with a red phantom. The phantom quickly won, and I was granted with 600k souls as a reward ^_^

@Turambar: I am a forest hunter, got summoned and found the host fighting with a red phantom. The phantom quickly won, and I was granted with 600k souls as a reward ^_^

I've heard that some people do the dragon head stone glitch to get 50,000,000 souls or more and then just run into the forest to die.
 
To the OP's point though that is really cool. I assumed multiple invasions were possible as you can be invaded by multiple Dark Moons as well as Forest Hunters but I've never heard of multiple covenants fighting it out before now.

I was summoned as part of the forest covenant.  After the usual bowing gestures, me and the host face off, only to see the note that another invader had arrived.  Not paying too much attention, I keep fighting.  Suddenly I see tranquil walk of peace being casted off screen, which hits both me and the host.  The person that casted it was not another forest invader, but a darkwraith.  Since both me and the host were slowed, I just started spamming wrath of the gods which killed both him and the dark wraith.  Ok, so maybe that's not really coexistence, but the game does allow for 3 way free for alls it seems.  Now, the quesiton is can we have someone being invaded by forest invaders, blades of the dark moon, and darkwraiths while having a white phantom and warrior of the sun on his side?  And perhaps they can just line up and do a merry jig instead of fighting and post it on youtube?  Pretty please?

A similar thing happened to me the other day. I invaded someone's dark Anor Londo as part of the Darkmoon covenant. When I met the guy in the main hall, a red phantom spawned behind him and we ransacked him from both sides.

Now whether or not he somehow managed to get away and I somehow managed to fall off the map, I can't remember, but it's the thought of jolly, unplanned cooperation that counts, right?

Yet another fun fact in line with the previous notice.  It would appear that souls from pking are shared even in a 3 way free for all.  I invaded someone as a spirit of vengence.  He was fighting a dark wraith.  Upon him killing the dark wraith so the two of use could duel like gentlemen, I got 20k souls.  
 
The more you know.

Ya, I have had similar experiences when being summoned as a black phantom for dark moon blade covenant.

Dude killed me and my target.

Edit: oh as for your bottom question, unfortunately the forest covenant requires your target to be in the forest and dark moon requires your target to be in anor lando so those two wont mix, but it may be possible to get a red phantom, a dark phantom, a target and those dragon summon things that I don't know what they are but I think they are PvP summons for duels or something, so you could potentially have a 4 way that way.

In theory anyway.

@The_Laughing_Man said:

@Turambar said:

I was summoned as part of the forest covenant. After the usual bowing gestures, me and the host face off, only to see the note that another invader had arrived. Not paying too much attention, I keep fighting. Suddenly I see tranquil walk of peace being casted off screen, which hits both me and the host. The person that casted it was not another forest invader, but a darkwraith. Since both me and the host were slowed, I just started spamming wrath of the gods which killed both him and the dark wraith. Ok, so maybe that's not really coexistence, but the game does allow for 3 way free for alls it seems. Now, the quesiton is can we have someone being invaded by forest invaders, blades of the dark moon, and darkwraiths while having a white phantom and warrior of the sun on his side? And perhaps they can just line up and do a merry jig instead of fighting and post it on youtube? Pretty please?

So ya...Three ways confirmed?

I was naked sword fighting a dude in the Kiln. We were both using katanas and just had a shield and havel's gauntlet. During our fight a Darkmoon invaded the host. The darkmoon used a black knight to try to kill the host so I backstabbed the Darkmoon and the host finished him off. We then continued our dual.

I had this happen again last night. Dude that invaded didnt touch me just helped me kill the host and we bowed to each other and parted ways. 3 way is definitely confirmed (its even mentioned casually on the wiki) but I still am curious if a 4 way is possible Hmm it may even be possible to have 5 if the host has 2 other people summoned.

Hmm the possibilities of random encounters

Yesterday I (darkwrait) Invaded a guy with a sunlight warrior who was fighting a Darkwrait and a Darkmoon. so, 2 darkwrait, 1 darkmoon, 1 Sunlight and a Host. Pretty cool :)

Yesterday I (darkwrait) Invaded a guy with a sunlight warrior who was fighting a Darkwrait and a Darkmoon. so, 2 darkwrait, 1 darkmoon, 1 Sunlight and a Host. Pretty cool :)

I'm actually doing pvp in Anor Londo (sl 40) and i find alot of funny situations almost 1/2 of the times. Last night i found a host who was fighting vs a DarkMoon, and 2 DarkWrait who was fighting eachothers (yes, the DarkWraits are not "mates"). i just jumped in with my Sword dance XD

I had someone invade me while i was in the catacombs and i was hiding where the slow movement miracle was and he was running around the area for a good 30 minutes then someone else invaded and they started attacking each other on the bridge.. I went to the opening and used the dragonbone bow and started shooting them.. first guy took 2 shots before he noticed but he was pushed off and second guy must have had him targeted because he kind of just walked off the edge after him. Still wish my main guy could De-level like in demon's so I could bring him into more pvp fights as 290SL is not easy to find fights in.

I've always wanted a three-way, but this isn't what I had in mind. Anyways, I was summoned as a spirit of vengeance in Dark Anor Londo, and when I got there, there was a Dark Wraith but I couldn't target him.