three wishes and other cards that say "you may play"

[TheRogue]

I have this odd ball cards name three wishes.

http://gatherer.wizards.com/Pages/Card/Details.aspx?multiverseid=3652

Basically with the removed cards. It say you may play them until your next upkeep. If played on my opponents turn does this mean I could pay and exiled cards of say the mox (artifact) variety on there turn? (when you wouldn't normally play it)

This wording is confusing to me. I was once told you can respond to a Phyrexian dreadnoughts sacrifice ability by activating a Mosswort bridge and playing another Phyrexian dreadnought in response (that was under the bridge via exile ability). Much less followed up by being told I could play it via mosswort on an opponents turn.

http://gatherer.wizards.com/Pages/Card/Details.aspx?multiverseid=139515

When dealing with such cards that say "you may play-" how are these best approached? Is what I am playing with such abilities not bound by its traditional timing of being played if just for the spell/ability with that wording?

[LotusHead]

This very type of question was discussed here:

http://www.themanadrain.com/index.php?topic=39821.0

My recent standard play has brought up a question, for which I've been given a contradictory answer to. 
This card's activated ability is worded like Mind's Desire with regards to playing the card that is revealed, more or less.  I had asked a judge and was told that I could play a land that is revealed with the Djinn even if I had already played one for the turn and don't have another card that would allow me to play more than one land a turn.  I followed up the question with, "does me playing the revealed card have to be a legal play?  For instance can I play a creature, enchantment, sorcery, etc on my opponent's turn with the Djinn?"  I was told yes that I could. 

If you reveal a land with Djinn of Wishes and have already played a land this turn, you are not able to play the revealed land unless you have some other effect which allows you to play an additional land, and can never play a land when it is not your turn.

Djinn of Wishes' and Mind's Desire's wordings are not the same.  Djinn of Wishes reads, "You may play that card without paying its mana cost."  Mind's Desire reads, "Until end of turn, you may play that card without paying its mana cost."  The Djinn is telling you to play the card right now, so you must play it during the resolution of the activated ability (or not at all).  Mind's Desire gives you a duration on when you can play it (until end of turn).  So with the Djinn, you can cast a sorcery, enchantment, creature, etc. even if it's not your main phase, since it ignores timing restrictions.  (It's during the resolution of an activated ability, not a time when you could normally cast any spell, even an instant.)  Mind's Desire is not telling you to play the card right then, it's setting up a duration within which the card can be played, so any timing restrictions must still be obeyed.

For Three Wishes:

Basically with the removed cards. It say you may play them until your next upkeep.

So that would be no, you couldn't play the artifact outside of your main phases.

[Killane]

The important thing with an effect like this is to distinguish weather or not it allows you to play the spell as part of the effect resolving, or if the effect resolving sets up a time period in which you can play the spell. If you play the spell as part of the effect, it follows that you do so during the resolution of the effect and therefore ignore timing restrictions. If the effect sets up a period of time in which you may play the spell, then the effect itself must resolve first, and therefore you need to obey timing restrictions. Remember that principle and you'll get the answer to this right every time.