can you use a blinding mage to tap a creature thats attacking you?

[Berserk]

can you use a blinding mage to tap a creature thats attacking you?

[Void Elemental]

Yes. Assuming the creature doesn't have vigilance, it should already be tapped. Note that tapping a creature already attacking you won't prevent it from dealing damage or throw it out of combat.

[Arix]

If you want to stop a creature from attacking, you'll need to tap it before it's declared as an attacker.