Dimensional Travel in Marvel Heroic Roleplaying

In the Dark Salvation Event I have been running, there is a lot of dimension hopping.  So, it seemed worth having an extra mechanic for that.  Because that's what you always need, right?  An extra mechanic?

Dimensional Borders and Gateways
Every Dimension has a Border value of at least two dice, that represents the difficult of getting in to the Dimension.  A very difficult dimension to enter may have 2D12 or 3D12 as it's border value, while a pathetically easy one to enter my have 2D4.   Most Dimensions have a Gateway, a "normal" (whatever that means in the context of dimensional travel") method of entering and exiting that dimension.  The Gateway need not be a "physical" (again, whatever that means) doorway of some sort.  It could be a state of mind, an object one needs to possess, a ritual to perform, etc.  Some examples:

The Dark Dimension
Border: 3D12
Gateway: The G'Uranthic Guardian

If you go to the trouble of having a dimension that is hard to get into, why would you make the doorway so obvious?

Muspelheim
Border: 2D8
Gateway: the Roots of Yggdrasil

Not the sort of all-inclusive resort spot you were hoping for.

Sominus
Border: 2D4
Gateway: Sin of any kind, the road to hell is wide

Sominus needs labor-law reform in a big way.

Dimension Travel
The character arranging for the dimension travel rolls against the Doom Pool of the new dimension.  If you are moving to a new Act as part of the dimension travel, that would be what the Doom Pool will be after the hop, otherwise it will be the current Doom Pool.  You add the Border dice of the dimension to the Doom Pool for the roll.  However, if you are already at the Gateway to that dimension, you do not.  

This roll is an Asset creation roll.  If you succeed, you can create an Asset that represents your successful arrival into the dimension.  For example, "Just where we planned to arrive" or "Thog is surprised" or "Dimensional Currents are Smooth".  

On a failure, it means you were not able to enter that dimension.  You will have to go somewhere else (usually a different dimension) and try from there, or somehow get to the Gateway if you were not there already.  However, the Watcher can choose to allow you to arrive in the dimension anyway.  If the Watcher does this, the Watcher can use his/her Effect die against you for free to create a Complication, Asset, Stress, etc.