question about an effect that can be used once

[rax_7]

some card have an effect that says, "One time only" or "Once in a duel" or something like that.

if the monster is returned to my hand, and i resummon it, that should be considered as a new monster, right? can i activate the effect again?

[Strider Tigerwolf]

Nope. That's the same as trying to reuse Glow-Up Bulb's effect when it can only be used once in a Duel. Even if you have multiple copies, it can only be used once in a duel, no more no less.

Cards that say "One time only" are different because these CAN be reset. Like D HERO Dasher's effect. Once he's out of the Grave, his effect is reset for another use.

[evilfusion]

No.

Rule of thumb is this:

If a card states that "Card X" (says the card's name specifically) can only be used once per turn/Duel, it can only be activated by you once per turn/Duel, even if you use a different copy of that same card.

If a card just says "Once per turn" or similar, it refers to each instance of that card. Different copies of that card (or the same copy flipped facedown or re-Summoned) can use the effect once each.

[Toffee.]

The only obscure chance in which you can re-use a one-time effect, is with Suijin, Sanga of the Thunder, or Kazejin.
As each of them says you can only use their effect once, [i]for as long as they remains face-up on the field[/i].