If Obelisk the Tormentor is summoned while field card future visions on will be negated by effect?

Yes, Obelisk the Tormentor's effect will negate the effect of "Future Visions" if it's summoned while "Future Visions" is on the field.

Here's why:

* Obelisk's Effect: Obelisk's effect states, "This card cannot be destroyed by card effects."

* Future Visions' Effect: Future Visions' effect is a continuous effect that activates during the End Phase of each turn, allowing you to draw a card. This effect is considered a card effect.

Conclusion: Since "Future Visions" activates its effect during the End Phase, it is considered a card effect. Obelisk's effect negates any card effects that try to destroy it, including the effect of "Future Visions."

Therefore, when Obelisk is summoned while "Future Visions" is on the field, the effect of "Future Visions" will be negated.