Infinite turns - Standard

I may be wrong but I don't think this works since youhave to return Magois to your hand when you remove the Ion counter.

Yes, i think if you have an Amulet of Vigor out in play it would make this work. or at least somewhat work. But it would work just as well for your foe since you have to skip an infinite amount of turns to get an infinite amout of turns.

Since Magosi returns itself to your hand as part of the cost to get that "free" turn, you really need to pair it with Amulet of Vigor and Rings of Brighthearth to negate the draw back. You'll still lose 1 turn, but with Rings, when you take your extra turn, you can get a second off of Rings, letting you replay Magosi (in that same turn) and prime it for another use (via Amulet). The net result is +1 turn (2 free turns, then you skip 1). However, that brings you out of Standard. But as of right now, there is no good way to abuse Magosi in Standard anyway. Odds are Magosi's "free turn" ability was costed the way it is because of Proliferate waiting in the next block.

lol i had the exact same idea but use Magosi with Contagion Engine to get two counters on it then maybe pairing it with Garruk to untap to get an second extra turn but got caught on the return to hand.

Proliferate will do nothing to Magosi, because as has been said before, it is returned to your hand as part of it's activation cost. When it is returned to your hand, all counters are removed from it.

Amulet of Vigor would not work either, as 1) you can only play one land per turn, 2) you still have to skip your next turn to gain an extra turn. Even if you used an ability to untap the land, you would still have to skip the extra turn you just gained.

As Anubuss said, Rings of Brighthearth would enable you to take an extra turn without having to skip one, but in order to do so you would need some way to untap the land. I'll play it out for you:

With a method of untapping Magosi--
1) (Magosi) {U}, {T}: Put an eon counter on Magosi, the Waterveil. Skip your next turn.
2) Untap Magosi.
3) (Magosi) {T}, Remove an eon counter from Magosi, the Waterveil and return it to its owner's hand: Take an extra turn after this one.
4) (Rings of Brighthearth) Whenever you play an activated ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Result: Skip your next turn, and gain two extra turns. You skip one of your extra turns, and end up taking one extra turn after this one. To gain infinite turns through this method, because Magosi etb tapped, you would either require Amulet of Vigor in play, or a second of either Magosi or Rings and {4}{U} spare mana to spend.

Without a method of untapping Magosi--
1) (Magosi) {U}, {T}: Put an eon counter on Magosi, the Waterveil. Skip your next turn.
2) Skip your next turn
3) (Magosi) {T}, Remove an eon counter from Magosi, the Waterveil and return it to its owner's hand: Take an extra turn after this one.
4) (Rings of Brighthearth) Whenever you play an activated ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Result: You skip your next turn, then you gain two additional turns on your turn thereafter. To gain infinite turns through this method, you would still have to skip your next turn, and two Rings in play and {4}{U} spare mana to spend.

I'm pretty sure the above assessment is correct, but maybe not.. I was trying to construct flow charts in my head :P In either case, it's not happening in standard, and requires such a hefty setup (let alone, most likely too many cards in your library contributing nothing else to the deck besides the combo) to be worth while. You'd be much better off just running 4x Lighthouse Chonologist.

Mr_Aqua has deleted this comment.