So, your next project is a Pox/Jokulhaups deck that creates chaos in multiplayer.  I think I can help you there.  Cards like Pox and Jokulhaups are great for multiplayer, so this ought to be fun.  As you said, you want to mess up everyone, including yourself, as long as you can stay on top of it.  Well, this is easier than it sounds, since you’ll be the only guy on the tightrope with an umbrella, so to speak.  Your opponents won’t be expecting Pox and Jokulhaups, they’ll be trying to churn out hordes of Saprolings or whatnot.  Most multiplayer decks take advantage of the slower format to try and build up huge armies.  they’re used to having plenty of resources.  You get to be the guy who saw the disaster coming.  Your deck will have to be built to run on very few resources, so you’ll be able to recover fastest.  How do you do that?
 

-Indestructibility

Being indestructible won’t stop the Pox, but it does stop Jokulhaups.  If you’ve got a few indestructible lands or artifacts on the board, then after a Jokulhaups you’ll have a headstart on everyone else.
 

-Alternate mana

Both Pox and Jokulhaups go after lands.  By having other types of permanents that produce mana, you can umleash plague and pestilence fearlessly.
 

-Baubles

“Baubles” are a term for small, 0- or 1-mana artifacts that can be sacrificed for an effect.  Most of them can be sacrificed to draw a card.  So having plenty of these is like storing a card in your hand on the board, where Pox can’t get it.  And by sacrificing them in response to your own Jokulhaups, you allow yourself to refill your hand with cards, giving you plenty of options in a post-apocalyptic world.

-Enchantments

Neither Pox nor Jokulhaups can do a thing against enchantments.  If your opponents have a lot, that’s trouble for you, but you can play enchantments too.
 

-Death as a doorway

Some creatures like to be sacrificed, and others can bring themselves back from the ‘yard.  Some cards can even bring creatures from other players graveyards into play under your control.  Stock up on these by all means.

 

Okay, so what kinds of cards specifically should you use?

 

Darksteel Citadel, Ingot, & Brute

The Citadel is simply an indestructible land.  The Ingot is an indestructible artifact, that produces mana.  The Brute is especially nice, since you can pay mana to make it a creature, but it’s always indestructible.  Not only can it hold off huge attackers and live, you decide when it’s a creature, so you can let it dodge Pox, or you can sac it to Pox instead of your good creatures.  Remember, Pox rounds up, so if you have three creatures, Opponent A has four, and Opponent B has five, Pox puts you all back at two.  Ideally you want all four of your Poxable resources to be at a multiple of 3, so you don’t get hit harder than need be, and the Brute helps you do this.

 

Mana Flare

In multiplayer games, a funny things happens when you play Mana Flare.  One, your opponents decide to focus their offense away from the guy giving them plenty of free mana and towards each other, which obviously works in your favor.  And two, they tend to play out all the cards in their hands.  If they play all the cards in their hands, they lose more creatures to a Jokulhaups, and leave themselves without any options to recover.  Also, it’s an enchantment, so it lives through the ‘haups and the Pox.

 

Conjurer’s Bauble, Necrogen Spellbomb, Pyrite Spellbomb...

These are the baubles I mentioned earlier.  You’ll need to use them before a Jokulhaups, but they live through a Pox.  Good thing too, because Pox is an incredibly disruptive card that leaves everyone scrambling to regain control.  If you can press the advantage right after the Pox, by sacrificing a Spellbomb, then you could make it effectively impossible for them to recover.

 

Spinning Darkness

Pox leaves everyone with low life totals.  A red burn spell or a black “life drain” spell can help give you the upper hand.  I chose Spinning Darkness mostly because it can be played without mana for after a ‘haups, but any cheap red burn would work as well.

 

Honden of Infinite Rage/Night’s Reach

Again, enchantments aren’t bothered by Jokulhaups or Pox, and these two help to deny your opponents of the very same things that Pox does; cards in hand and life totals.

 

Homura, Human Ascendant & Kuon, Ogre Ascendant

Homura wants to die, and Kuon wants to witness a lot of death.  Once they do, they become enchantments.  As enchantments, Homura makes even a 1/1 of yours a force to be reckoned with, and Kuon forces sacrifice after sacrifice.

 

Brood of Cockroaces

A simple 1/1, but it has an ability that brings it back from the graveyard.  So it can be sacrificed to a Pox or die to the ‘haups as often as you like, and keep coming back.  Also try Endless Cockroaches; they’re very similar but I can’t remember right now which one I prefer.  Pick the one you like I suppose.

 

Beacon of Unrest

With all the things going to the graveyard, you’re sure to find something of yours or your opponent’s worth resurrecting with this little number.

 

Nightmare Void

A simple discard spell, but powerful here because it can come back from the graveyard.  You can use it as many times as need be to empty your opponent’s hand.

 

Okay, so let’s try to put together a decklist.

 

Creatures

4 Brood of Cockroaches

3 Bottle Gnomes

1 Homura, Human Ascendant

1 Kuon, Ogre Ascendant

 

Other Spells

3 Pox

2 Jokulhaups

3 Mana Flare

4 Conjurer’s Bauble

3 Negrogen Spellbomb

3 Pyrite Spellbomb

2 Darksteel Ingot

3 Darksteel Brute

1 Honden of Night’s Reach

1 Honden of Infinite Rage

2 Beacon of Unrest

1 Nightmare Void

3 Spinning Darkness

 

Lands

2 Darksteel Citadel

9 Swamp

9 Mountain

 

I didn’t know how many Pox or Jokulhaps you had, so I had to just make up numbers.  You’ll have to play it and see how it feels to work with the numbers, adjusting it as you see fit, since I can’t be sure how it’ll play out.  Good luck!