Uncanny X-Men Vol 1 #274

Zaladane has erected six towers in the Savage Land and is now in sync with earth's magnetic field. With her magnetic powers she has scrambled all communication within the Savage Land, and the effects of her mad quest for power are already felt far away!

It's an epic battle is being waged in the Savage Land and the future of mankind may rest in the hands of...Magneto?! Meanwhile, the X-Men have arrived on the far side of the universe only to have blundered into the trap of an old and dangerous adversary.