Strange. I wonder how many people would think to use this to turn their own lands into Islands. You could power out some UUUU spells in a reasonable amount of time with a three color deck, this aura, and a Merfolk Looter.

Mind you, I don't think that's worth building a deck around (well, depending on the cards), I'm just musing.

There was only so many card slots in common... Sit set is odd because gold and artifacts sucked them all up. Had we any more room, I probably would have put in a card that rewards the opponent for having islands. With only 14 cards to work with, though, this card would be too much of an outlier. I'm bumping to uncommon to see if the mechanic still has legs up there.

Why the "target non-Island land" bit? It evokes Quicksilver Fountain, but Flood doesn't stop the flooded lands tapping for their original colour of mana.

I don't know.

It looks to me like the idea was to make the flood keep spreading (which is usually what you want, but might matter if you had multiple of these cards or some other reason not to want your opponent to keep getting more U).

I think it might be a general question for flood, rather than for this card: should you be able to flood a land multiple times? (If so, won't it look odd? If not, can you not cast flood cards if your opponent only has flooded lands? Perhaps the template for flood should be "put a flood counter on target land if it doesn't already have one"?)

Hmm. Searching Oracle for "for as long as it has", we find that Aquitect's Will, Aven Mimeomancer, Liege of the Tangle and Dread Wight are happy to let you keep targeting the same target successive times. The only ones that prevent it are Quicksilver Fountain and Cyclopean Tomb, and they do it by saying "target non-Swamp land" / "target non-Island land"; in both cases that's to ensure the contagion spreads rather than out of concern to avoid double counters.

So I think this is saying that it's not worth the extra words just to prevent duplicate counters. Let the Power Conduit Johnnies have their fun if they want to.

It would be a problem if we designed into it, but, if we don't give people a specific reason why they would want to dump a bunch of flood counters on one land, then it's probably fine. Note to self: Do not design a card that says "Whenever you tap a land add to your mana pool for each flood counter on that land."