Source: Unearthed Arcana 85 - Wonders of the Multiverse

Prerequisite: 4th Level, Scion of the Outer Planes Feat

You can draw on the forces of the multiverse to survive cosmic extremes and to traverse its infinite realms. You gain these benefits:

Planar Adaptation. When you finish a long rest, you gain resistance to either acid, cold, or fire damage (your choice) until you finish your next long rest.

Portal Cracker. Your experience with portals allows you to operate them without the proper portal key. As an action, you can concentrate on a portal you’re aware of that is within 5 feet of you and make a DC 20 Wisdom (Survival) check. On a failure, you take 3d8 force damage and you can’t use this feature on that portal again until you finish a long rest. On a success, you can force the portal open or closed for 1 hour. For that duration, a portal closed in this way doesn’t respond to its portal key unless a creature employing the key succeeds on a DC 20 Intelligence (Arcana) check as an action.

Portal Sense. You know the direction to the last planar portal you used while you and the portal are on the same plane. Moreover, as an action, you can detect the location of any portals within 30 feet of you that aren’t behind total cover. Once you detect a portal with this action, you can’t use the action again until you finish a long rest.