Rules Tip of the Day: If a card with a non-existent mana cost is given a Replicate or Flashback cost, these additional / alternate costs are also non-existent. And just as you cannot pay a non-existent mana cost, you cannot pay a non-existent alternate or additional cost.

Q: I attack with Hedge Troll and control an untapped Plains (so it's 3/3 with "W: Regenerate"). My opponent blocks with a 2/2. After blocks, he plays Ovinize on Hedge Troll. In response, I activate the Troll's regeneration ability. When Ovinize resolves, will it remove that regeneration shield?

A: No. When Ovinize resolves, the Hedge Troll will be a 0/1 creature with no abilities, but it will have a regeneration shield on it. It may not have the regeneration ability any longer, but the replacement effect that was generated by the previous activation of that ability will still be there.

Q: Can a Spider (a creature which "can block as though it had flying") block a creature enchanted with Dust Corona? That is, can it only block as though it had flying? What if the Corona'ed creature has flying?

A: Creatures with the Spider or "Web" ability that "can block as though they have flying" are treated exactly as thought they have flying when declared as blockers. This means that a Spider cannot block a creature enchanted with Dust Corona. This is true even if the enchanted creature has Flying. if it does, then this creature cannot be blocked by any creatures when blockers are declared.

Q: My opponent has a Loxodon Gatekeeper in play. I cast Dragonstorm with a Storm count of three, for four total Dragonstorms. I get three Bogardan Hellkites and a Hunted Dragon. Can I choose the stack to get my Hellkites and put lethal damage on the Gatekeeper, and then bring the Hunted Dragon in last, untapped?

A: Yes, that works. When an individual copy of Dragonstorm resolves, one Dragon will come into play. When it does, comes-into-play abilities of this Dragon will trigger. The triggered ability of this Dragon will resolve, and state-based effects will be checked before the next Dragonstorm copy resolves. So if you deal lethal damage to the Gatekeeper in play when the first Hellkite comes into play, then the subsequent Dragons will come into play untapped. Often players take the shortcut of resolving a Storm spell and all of its copies at one time. In many cases, this is fine, as long as both players understand what is going on. But this is an example where knowing exactly what happens and being clear about it can make an impact on the game.

Q: If an opponent has five life and I cast Fiery Justice on him, does his life goes to zero, winning me the game, or he survive?

A: Your opponent will not lose, and the game will continue. When Fiery Justice resolves, five damage will be dealt as you chose when you played it, and your opponent will gain five life. Then, after Fiery Justice has completely resolved, state-based effects will be checked. At this point your opponent's life total will be five, so he will not lose the game.

Q: The various rulings for Soul Warden state that it "will trigger on any other creature that is put into play at the same time Soul Warden is." However, the rulings for Nether Traitor state that "If Nether Traitor and another creature are put into your graveyard at the same time, Nether Traitor's ability won't trigger." Why is there a difference?

A: The difference is that Soul Warden has a comes-into-play ability: it only cares about something coming into play. Nether Traitor has a leaves-play ability: it cares about something leaving play and going to the graveyard. Comes-into-play abilities check the game as it currently exists and look to see if the ability has just triggered. They have to work this way so that comes-into-play abilities of a permanent will trigger when that permanent comes into play. For example, look at Nekrataal. In order for its ability to work, it has to come into play and then you have to check the current game state. As Nekrataal did just come into play, its ability will trigger.

Leaves-play triggered abilities are a bit different. In order for them to work you have to look at the game state just prior an event to see if the trigger condition is met. This is because when the ability actually triggers, the permanent with the ability may not actually be in play. For example, when Cyclopean Giant's ability triggers, it is no longer in play. In order for this ability to work you have to look to just before the Giant left play to "see" its triggered ability.

In order for Nether Traitor's ability to trigger, the ability must exist before another creature would go to the graveyard. As this ability only triggers when the Traitor is in the graveyard, it will have to be in the graveyard before this other creature goes to the graveyard. This is why if Nether Traitor goes to a graveyard at the same time as some other creature, its ability will not trigger.

Q: My opponent plays eight spells during his turn, and plays a Grapeshot. In response, I play Quicken, then Mind's Desire. If I flip up a Sorcery with Desire, can I play it?

A: No. Mind's Desire allows you to play these cards that have been removed from the game, but it does not change when you can play them. As it is your opponent's turn, you will only be able to play those cards that can be played whenever you could play an instant.