Pointed Discussion

While not the best card in Magic it still has potential such as making a land produce the mana you need not sure about the rulings of how it affects your opponents lands but if it works like I hope it does it can make your opponents land a different type when they really needed that specific mana

I like to use it for islandwalk with other merfolk, but besides that it isn't all that helpful

great one drop in my U/W merfolk deck, in which I have several lord of atlantises. can also help if I'm running short on plains. 4/5

I can agree that this would work good would islandwalk and what not, but I think the real potential is in a deck with those creatures that can't attack unless the opponent owns an island. I'm not saying I play these decks but I think personally that this is what this creature is most useful for.

He's also good for hurrying out a Saprazzan Legate or two.

Not just fantastic with the legate cycle, try out Submerge!

What I love him most for, he can screw up counters.

fails to cancel

This only has limited usefulness in color-screwing your opponent. Mana abilities work immediately (without using the stack), so if you wait until after your opponent has tapped the land, it's too late, and if you do it before, they can tap it in response and still get the mana they want before you change it, and just float the mana. You could use this during their upkeep, but they'd still be able to use the mana to cast an instant.

EDIT: I overlooked the "only during your turn" clause. So I guess you could use this during your upkeep, to stop your opponent from using a counterspell or something, but...

See also Reef Shaman which is a 0/2, Dream Thrush which costs {1}{U} and has flying, and Sea Snidd which is a 3/3 beast for {4}{U}. Grixis Illusionist also does this, but only for lands you control and is thus useless for color hosing your opponents like you would with the others.

I have two of these in my U/W Merfolk deck. Seahunter is always great for bringing him out if I don't happen to draw him. Of course, he has great synergy with Master of the Pearl Trident blah blah blah.

However, my favorite part is when I use him to cast Gisela, Blade of Goldnight. Such a random combo, it always manages to throw my opponents off balance. 4/5