Activation of cost effects on opponent's turn

[Gendo Ikari]

At the last tournament that I played in, I lost due to what I thought was a rather odd ruling. As the ruling came from an official judge, I've been playing by it ever since. My opponent activated his Magical Scientist's effect on my turn to summon TER to prevent me from attacking. The next turn, he summoned the turtle, and it was over. I've also read that Tribe Infecting Virus's effect can be activated on my opponent's turn, as long as I can pay the cost. Is this ruling accurate? Can I activate effects like this on my opponent's turn? If not, then why even use Tribe? The cards themselves and the rulebooks do not limit when the cost has to be paid, and so there is no ruling aginst it, according to the judge I last spoke with. Has this ruling been overturned?

 

[densetsu_x]

Your opponent was wrong as was the Judge. The effects you are describing are considered "Ignition Effects" (formally "Cost Effects"). They are Spell Speed 1 and can ONLY be activated during your Main Phase 1 or 2. The only effects of monsters that can be activated during your opponent's turn are "Multi-Trigger Effects" (of which it would be stated on the card that you can activate the effect during your opponent's turn). That is how it has been since day 1.

 

[Gendo Ikari]

Thanks

Well, thank you for clearing that up. It's too bad that I didn't try for a higher level ruling at the tourney. It was my regional qualifier back in May of 04. One more clarification on this, however, concerning cards like Relenquished that say "once per turn" and not "once per your turn" would be helpful. Can I activate Relinquished's effect on my opponent's turn? (sorry if I sound like a newbie)

 

[densetsu_x]

That part of "Relinquished"'s effect is another Ignition Effect so the same rules would apply.