Make no mistake: this is Teferi's Response to Rishadan Port. It also punishes Dust Bowl and ordinary land destruction, but those are secondary targets. The question is what role this card will get to play in the format. Is it a sideboard card or a maindeck card? You can maindeck Teferi's Response only if you'll be responding a large majority of the time. This would mean that most of your opponents are playing Ports, since anyone who uses other land destruction will use those first. Right now there's more than enough Ports for this card, largely because there's no risk beyond not getting colored mana. That's going to change, and a deck that would be indifferent (such as Replenish was) would probably choose to avoid them instead.
If this card is maindecked a significant portion of the time, those decks that do play Ports (and there's no question many will) have to decide whether to use them when facing Islands. It's would seem to be an all or nothing question, except for when the blue mage has only one mana or cannot afford to tap two lands even to draw three cards. If you start using Port early on and risk a Response, you'll use them well into the midgame. If you hold back at the start, you're better off never targeting your opponent's lands at all. Where will the balance settle? If there are so many maindeck Responses that Ports do not get used against blue decks, then Response is no longer needed in the deck, so that situation is not stable. If Ports can be used automatically and remain in as many decks as they are in now, Response becomes an automatic maindeck card. That leads back to the first situation, so this too is not stable. What's more likely is that Ports will be used almost but not quite as much as now, and against blue they will be used carefully, more carefully after boarding than before. The way to use them carefully is to exploit the secondary weakness of Response (the first being that it is often useless, even if your opponent is playing Ports).
The problem is that this card is blue, so not all decks can use it, and while it's devastating in the long term, your opponent will get an opening. Here's the issue. Suppose I use Rishadan Port at the end of your turn. You play Teferi's Response, destroying it and giving you two cards. I untap and cast Armageddon. You drew two cards, and that's better than nothing, but you're still going to lose. The Response made you vulnerable in the short term, because you tapped two mana instead of one. This means Response is an answer to Rishadan Port but not to the threat of Rishadan Port. I may no longer be able to automatically use them on your upkeep, but you still have to set an extra land aside for each one if you want to have mana on my turn. If I have enough mana to use it on my turn as well, you still need to set aside two. The only time when it gives you breathing room is if losing the Port would make me unable to cast my game winning spell, but that doesn't last very long. There are other problems with it as well. It isn't immune to counters and it doesn't give you mana, so using this against a Rising Waters strategy is also questionable. The list goes on.
All of that makes the card of questionable use. What good is it if it doesn't let you keep your mana untapped when it matters? One solution is to use this to make up for a card economy loss. In particular, you can use this to balance out Foil, using the extra two cards from Teferi's Response to fuel Foil's alternative casting cost. This also justifies Foil: in the matchups where your mana is under attack, you can now afford the card loss. In Extended, you can also stop Wasteland and can use Force of Will instead of Foil. There's more competition for slots in an Extended deck, but the card also becomes stronger. If it isn't, you have a good chance to pay four mana. There are three ways out of this problem. One is to play against someone who uses Rishadan Port without worrying about Response and therefore will not choose his moments well. Depending on how much play Response sees this may or may not be practical. A second way out is to watch for when destroying the Port shuts down their ability to punish you by taking away their mana, especially in combination with Daze. This can force them to not use Port early when it's at its most effective otherwise. The last way is to note that your opponent has nothing that can punish you enough for being tapped out that you can't make up for it, but I would expect most decks to have bombs in them. A second and more promising possibility than those is that a traditional blue deck is not where this card belongs.
For example, you could put this a green based deck with blue mana sources, which could even be 'hidden' in the form of Birds of Paradise, City of Brass and other mana creatures. You could put it into a rebel deck that splashes blue for utility. You could put this into a blue creature deck such as Fish, using this to refuel your hand and destroy a land. You could put it in a Blue/Black long term card economy deck. The list goes on, and may include several new ideas based on other Invasion cards. In particular, anywhere this card is not expected it becomes much better.
One last note is that this card is obviously also great against targeted land destruction. Given that the strategy right now is only viable because of Urza's Block cards (Plow Under and Avalanche Riders) this strategy is probably going to have to fall back on mass removal such as Tectonic Break or Armageddon to have a chance, making this card ineffective against them - except their Ports, of course.
Tomorrow: Sleeper's Robe enchants Gary Wise.
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