What do the villains have?
 

Party Poker 0.5/1 Hold'em (9 handed) converter

Preflop: Hero is SB with A[img]/images/graemlins/diamond.gif[/img], A[img]/images/graemlins/heart.gif[/img].
<font color="#666666">1 fold</font>, UTG+1 calls, <font color="#666666">1 fold</font>, MP2 calls, MP3 calls, <font color="#666666">1 fold</font>, <font color="#CC3333">Button raises</font>, <font color="#CC3333">Hero 3-bets</font>, <font color="#666666">1 fold</font>, UTG+1 calls, MP2 calls, MP3 calls, <font color="#CC3333">Button caps</font>, Hero calls, UTG+1 calls, MP2 calls, MP3 calls.

Flop: (21 SB) 5[img]/images/graemlins/heart.gif[/img], 5[img]/images/graemlins/diamond.gif[/img], 7[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(5 players)</font>
<font color="#CC3333">Hero bets</font>, UTG+1 folds, MP2 calls, MP3 calls, <font color="#CC3333">Button raises</font>, <font color="#CC3333">Hero 3-bets</font>, MP2 calls, MP3 calls, Button calls.

Turn: (16.50 BB) 8[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">Hero bets</font>, <font color="#CC3333">MP2 raises</font>, MP3 calls, Button calls, Hero calls.

River: (24.50 BB) 8[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
Hero checks, <font color="#CC3333">MP2 bets</font>, MP3 calls, <font color="#CC3333">Button raises</font>, Hero calls, MP2 calls, MP3 folds.

Final Pot: 31.50 BB

My specific questions are:
What does the button have and why?
What does MP2 have and why?
What is your line, given the play of MP2 on the turn, and then the button on the river?

assume this is the second orbit, so you dont have any reliable reads.
From what you have seen: MP2 hasnt seen many flops, and hasnt shown any "bad" hands. Button is semiloose agressive.

Re: What do the villains have?
 

It looks to me like Button has KK or QQ. MP2 is tougher. I might be inclined to think that he's slowplaying 77, and then slowed down on the river thinking that the button was packing an 8.

By the way, what is MP3 doing tagging along for so many bets and then folding for the last one on the river? Sounds like the kind of player you could get quite a few chips from.

Re: What do the villains have?
 

Nothing can possibly make sense for Button. There's not a hand in the world I would play like him. But I'll say KK because he capped preflop.

MP2 limped and coldcalled two more. You said he hadn't played bad hands, but I don't think you should have included that read, as 9[img]/images/graemlins/diamond.gif[/img]6[img]/images/graemlins/diamond.gif[/img] is a bad hand.

Re: What do the villains have?
 

I put button on KK, but im not sure why he didn't cap on the flop. Also, he played like he was scared of something better than his pair on the turn and river. I'm pretty sure you had him beat.
MP2 plays kinda weird. He cold calls preflop and flop, and the 8 [img]/images/graemlins/spade.gif[/img] somehow causes him to bet out, and then he doesn't reraise on the river. I can't really correctly guess, so ill say he has A 7.

Re: What do the villains have?
 

Button's game is choppy: his play doesn't make sense one bit. Perhaps he has KK/QQ/JJ and raised the river because he saw you slowing down.

MP2 wakes up on the turn; so if he's an idiot he has an 8 and a blank. 96(s or o) is possible since he limped and many party players play any two. Also a 5 is possible since he limped.