How House Excession made its Portal Door.

The well of many worlds is embedded in the door the Dwarven Master  Masons have built. The sorcerer supreme embeds the door knob made by the artificer, as the druid's chant drawing in the power of the ancient ley lines below. The wizards weave their spells of binding while five bards stand at the outer edge of a circle, their music weaving streamers of light in a barrier around where the others work, it twists and throbs to a beat and all within it move to it in an a dance of incomprehensible beauty.

A 12 clerics arrayed just inside the circle watch, weapons a glow throbbing with the power of their chosen Gods waiting guardians mumbling prayers under their breath, all in deep communion with their faith. One monk sits in prindu bada floating just off the ground questing other planes for signs of those who would use this door for wrongness. There are no bodies here but seven warlocks are drifting among the planes around this one guarding for what cannot be seen.

Inside the door knob is a small core of pure magic, twelve strands woven tightly into a ball of infinite possibilities, possible worlds, it pulses and writhes with a combination of magics never seen before in any reality. It is a masterpiece of magic, a creation of something beyond the understanding of even the Gods who contributed to  it.

The door is inserted and swings. Through every world and every reality in the multiverse there is a brief thrumming of power through every being and a whump, as the door closes. The feeling is gone as if it never happened, for the only time in all of the realities every creature on every world shared that one moment, aligned in the closing of the door. Then the paths diverge and realities go their separate ways. Only these few here witness to it having any idea what happened. But even they know not what they have wrought. Excession.