Lorwyn/Shadowmoor block, which was an experiment both in block structure (it was a four-set, or two two-set blocks, depending on how you look at it) and design. Each color pair got highlighted with its own identity, different from those laid out in Ravnica: City of Guilds.
Several mechanics came out of these sets, including one combo fans everywhere love: Persist. Let's break it down.
Hang in There with the Persist Mechanic
Persist is a triggered ability. Long story short, it says if a permanent with Persist goes to a graveyard and doesn't have any -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.
So, you play out a Putrid Goblin on turn two. Turn three, you attack with it, and it dies in combat. You return it to your battlefield with a -1/-1 counter on it, ready to attack again the following turn!
Keep on going
Seems simple, but there are a few tricks about it.
First off, every card with Persist - currently - is a creature. However, there is no requirement the permanent be a creature. If a creature with Persist becomes a noncreature and goes to the 'yard, Persist will still trigger and it will return to the battlefield with its counter. The same is true with things like Vehicles.
Similarly, if a noncreature permanent becomes a creature somehow, it can gain Persist. (There are a few cards which grant Persist, like Cauldron Haze or Cauldron of Souls.) So if you activate your Inkmoth Nexus and somebody rudely kills it, you can cast Cauldron Haze and the card returns to the battlefield with a -1/-1 counter. As long as you don't activate it again, it is a colorless land and the counter is irrelevant. Of course, if you activate it, it dies immediately.
If a permanent has multiple instances of Persist, each one will trigger separately, but all past the first won't have any effect because the creature will no longer be in the 'yard.
Tokens can gain Persist, and it will trigger when the Token touches the graveyard. However, due to the nature of tokens, before Persist even goes on the stack the token will cease to exist as a state-based action (tokens can't exist outside of the battlefield).
Hang on
The trickiest part of Persist is figuring out when it doesn't trigger.
If a card with Persist is Exiled, Persist won't trigger; Exile is not the same as dying.
Similarly, if a card with Persist is Exiled from the 'yard before it can resolve, Persist won't trigger.
If a creature dies because it gains -1/-1 counters, through a spell or combat with a creature with Wither or Infect, Persist will not trigger because the creature has -1/-1 counters on it.
Here's the really tricky one:
- If a 3/3 creature has a +1/+1 counter on it and receives a -1/-1 counter, then dies to Lightning Bolt, Persist will trigger because the counters "cancel each other out" and the creature no longer has the -1/-1 counter.
- If a 0/0 creature with four +1/+1 counters on it gets four -1/-1 counters on it, it dies as a state-based action before the counters cancel each other out, so Persist will not trigger because it does have -1/-1 counters on it.
Finally, when the creature returns to the battlefield, it returns as a brand-new object. That means it has summoning sickness, loses any Auras attached to it, drops any Equipment, things like that.
Knuckle down
Persist is a strong ability with powerful combo potential. Combined with something like Melira, Sylvok Outcast, a creature with Persist can die over and over and simply returns to the battlefield, because the -1/-1 counter can't be placed on it. That in combination with Kitchen Finks and a sacrifice outlet means infinite life, or with Murderous Redcap becomes infinite death to your opponents.
I'm personally a fan of Glen Elendra Archmage, which does an excellent job of keeping people from doing things they probably really want to do, and Puppeteer Clique, because playing with other peoples' stuff is always a good time.
The important thing to remember: if it goes to the graveyard and isn't a token, it will probably Persist!
Thanks for reading.