I like the idea of the Archenemy having a "Scheme hand" of 3. My playgroup has found that all too often, you get the wrong scheme at the wrong time and it's pretty much useless. The alternative being the Archenemy draws 2 and chooses one to resolve.
As for the life issue, it's a tough call. Certainly starting with a little more life helps, however more often than not it seems like it's just a matter of board position. We use fairly powerful EDH decks so once the Hero's are established, it doesn't really matter how much life the Archenemy starts with.
Mostly this game seems balanced when it's 3v1, again for my playgroup. Morep layers after 3 heavily favors the Heroes to win against the Archenemy. Any suggestions on how we can balance this out for more players without changing the amount of life each player starts with?
I'm trying to come up with a rule set to more or less balance 1v4 Archenemy, specifically for EDH. Why 1v4? Because if we have 3-4, we'll probably play regular EDH, but at 5, it gets a little awkward.
The existing problems with Archenemy are this:
1) The fact that schemes are flipped entirely randomly really skews which schemes are useful. Any of the destruction schemes, since they involve opposing permanents, are dead or near-dead flips in the first turn or two. Meanwhile, a turn one Embrace my Diabolical Vision or Perhaps You've Met My Cohort for a powerful planeswalker is basically game over, especially in EDH where the curves stray a little higher. Games basically devolve into whether or not the Archenemy can flip one of those two or Plots That Span Centuries into a bunch of early-game resources
2) The fact that most of the schemes have a "when set into motion" trigger means that they are vulnerable to being Stifled, which I find to be incredibly bad form. These are supposed to be diabolical masterstrokes, why can the Allies just brush them off with super-cheap spells?
3) The fact that the Archenemy has to deal with four opponents, while all four opponents can focus their efforts on thwarting him, makes it inherently difficult for the Archenemy to win a long EDH game. This means that well-tuned Ally decks can just counter every card the Archenemy plays, while still having multiple cards to play threats of their own. It's very easy for the Allies to land something cheesy like an infinite combo or a Sorin Markov and just close out the game.
Here's what I'm thinking:
1) The Archenemy starts with X Scheme Cards in his "Scheme Hand", where X is the number of opponents, in this case likely 4. This is also his maximum scheme handsize, which no card can alter.
2) Each draw step, the Archenemy also draws a Scheme Card. During the cleanup step, if he has more than his maximum handsize in schemes, he must discard down to his maximum handsize.
3) During his mainphase on an empty stack, the Archenemy may, once per turn, set a scheme in motion. Setting a scheme in motion and the resulting triggered ability both resolve without using the stack. This is to stop Stifle effects from hosing the Archenemy, and to improve the power of the removal schemes by making them split second. The fact that he plays one from a hand helps to improve the power of the removal schemes by letting you save them until you best need them, rather than flipping them up first turn to a worthless effect.
4) At any time the Archenemy has priority, if the Archenemy has at least X (his maximum/starting handsize) schemes in hand, he may set any one in motion face down to exile any one Spell, Ability, Emblem, or Permanent other than a basic land. This is untargeted and does not use the stack. This is to provide the Archenemy an out for infinite combos and other cheese, but at the cost of having to skip setting a scheme into motion if you want to do it again. Additionally, as this could feasibly be used twice during the Archenemy's turn (if he enters the turn with a "full" scheme grip, draws one, and does not use any), it provides the Archenemy extra protection against a set of Allies trying to Counterspell out every play he makes.
5) The Schemes "Perhaps You've Met My Cohort" and "Embrace My Diabolical Vision" cannot be set into motion for the first N turns, where N is 6 minus the number of opponents. So in a 4-opponent game, they may not be set into motion on the first or second turn. In a 3-opponent game, they may not be set into motion on the first through third, and in 2-opponents, not on the fourth either. This is to prevent the complete blowout of a turn one (or even two) Embrace/Cohort, especially given that much larger chance to have one
6) If playing EDH, the Archenemy's General cannot be tucked. If the General would move from any zone to the Library, he may instead be placed into the Command Zone. The Allies' Generals may be tucked as normal.