The biggest rules change this time out involves the Two-Headed Giant multiplayer variant. Sometimes cards need to check what a player's life total is. The old rules that covered this said that each player's share of the team's life total was considered to be half that life total, rounded up. This mostly sorta worked, and it mostly sorta made sense. Your part of the life total was half that life total, right? But it also did some weird, weird things. If your team had 11 life, the game considered your life total to be 6, and your teammate's life total to also be 6. Weird. If an effect caused you to double your life total, your team's life total would go from 11 to 17. Weird. I could go on, but we're changing that rule, so why dwell on the past?

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Instead, the system is changing to the simplest system possible. If something needs to know an individual player's life total, it uses the team's life total instead. Some examples of what this means:

* If your team has 11 life and you cast [card]Beacon of Immortality[/card], you'll gain 11 life and your team will wind up at 22 life.
* If you control [card]Near-Death Experience[/card], you'll win the game during your upkeep if your team has exactly 1 life.
* If your team has 17 life and you want to activate [card]Lurking Evil[/card]'s activated ability, you'll have to pay 9 life to do so (not 5 life, which is what you pay under the current system), leaving your team at 8.

Some rules about life totals aren't changing. OK, one of the rules about life totals isn't changing. Specifically, gaining and losing life still applies to each player individually, and the result is applied to the team life total. For example, if your team has 24 life and you gain 6 life, your team winds up at 30 life (as you'd expect). Your [card]Well of Lost Dreams[/card] triggers, but your teammate's Well does not.

As for the rest of the rules ....

If something sets one player's life total to a specific number (like [card]Magister Sphinx[/card] does), that player gains or loses the necessary amount of life to wind up at the new total, and the team's life total is adjusted accordingly. So if your team has 18 life and you're targeted by Magister Sphinx's ability, you'll lose 8 life and your team will wind up at 10 life.

If something would set the life total of each player on a team to a specific number (like [card]Sway of the Stars[/card] would, or [card]Biorhythm[/card] would), a team that's being affected picks one of its players and only that player is affected. Sway of the Stars works as you'd expect (your team winds up at 7). Biorhythm ... well, that doesn't work in Two-Headed Giant as it is (which is one of the motivating factors behind the system change), so it's no big surprise that it's still screwy under the new system. At least that's the only card in existence that tries to set the life total of each member of the same team to a different number.

If something would cause you to exchange life totals with your teammate, nothing happens. Additionally, [card]Reverse the Sands[/card] gets its own special rule: It can't affect more than one player on each team. And finally, if an effect says that a player can't gain life, no player on that team can gain life.