Olly here on the eve before the Prerelease of M12. Just thought I'd quickly put up the changes and additional mechanics that we will be faced with at 10am tomorrow morn (in the Whistle Stop Pub, by Portslade Station).
Firstly a simple one, they are changing "When [this card] is put into the graveyard from the battlefield" into "When [this card] dies" not a drastic issue but it's worth mentioning.
Next is "Hexproof". This is again a replacment phrase for "Can't be the target of spells or abilities your opponents control". Mostly a green feature in the past, on such cards as Troll Asectis and Asceticism, in fact if you search for Asceticism on Gatherer the discription has been updated to include "Hexproof" - http://gatherer.wizards.com/Pages/Card/Details.aspx?printed=false&multiverseid=215082.
Third is a re-hash of an oldy, "Bloodthirst". It's a mechanic found on creatures that provides additional +1/+1 counters, and this is how it works. "Bloodthirst X" means "If an opponent was dealt damage this turn, this creature enters the battlefield with X +1/+1 counters on it." The 'X' on your cards will be replaced with 1 or 2 or 3...
And lastly the return of Planeswalkers. Never really far out of view, some have been re-writen and revamped but either way there will be some found somewhere tomorrow, so it is probably worth me explaining how they work and how to kill them.
A planeswalker counts as a spell (whilst being cast) and a permanent (whilst on the battlefield), so it can be targeted by spells that address these card types/ things.
They do not have power and toughness, but do have a sort of life in 'Loyalty Counters'. Each 'walker will say how much life they start with in the bottom right corner. They have abilities that add or subtract counters from this 'Life'. Abilities that subtract life can only be used if they have at least that many counters on them. If an opponent has a 'walker, you can choose to attack it/him/her instead of your opponent, but the opposing player can choose to block as normal. Unblocked damage done to a 'walker results in that many loyalty counters being removed. Similarly if I had 'Shock' (a red instant that deals direct damage to target creature or player) I can choose to target my opponent, but on it's resolve I can change my target to a 'walker. I don't wish to tell you why I can (because it's long and really complicated) just know that it can be done. This would again lead to damage and lose of counters and hopefully a dead expensive card.
Ok, I think that covers everything, if not well, talk to me tomorrow morning. See you there printed card based gaming fans.
Olly for GGUK out