Dimensional Rift

Come on now, this is how we got a blown up Draenor!

And after experiencing Warlords, nothing of value was lost.

The devs told us exactly how Dimensional Rift works at the links below.

http://us.battle.net/wow/en/forum/topic/20743504316?page=9#164
http://us.battle.net/wow/en/forum/topic/20743504316?page=12#225
http://us.battle.net/wow/en/forum/topic/20743504316?page=13#244
http://us.battle.net/wow/en/forum/topic/20743504316?page=21#415

I'm pasting it here as they typically delete the beta forums after release.

Dimensional Rifts will inherit their master's crit chance.

Artifact traits that buff an ability which is replaced/removed by a talent will instead buff that talent, typically. The Imp-related traits for Destruction likely don't yet, but eventually will, buff Grimoire of Sacrifice/Supremacy.

Chaos Tear fires spell 215279 once; it's intended to always crit but there's currently a bug preventing that.

Chaos Portal fires spell 187394 every 0.25s for 5.5s. Shadow Tear fires 196657 every 2s for 14s. Both of these will increase their cast rate with haste in the next build.

Each portal has an equal chance of appearing.

Q: Does the Chaos Bolt cast by Chaos Tear benefit from normal multipliers to Chaos Bolt damage? IE crit chance / mastery / artifact traits.

It does scale with your crit chance, not with your mastery or artifact traits that buff your Chaos Bolt.

Q: On the topic of pet multipliers, it appears dimensional rifts are functionally pets. They benefit from the orc racial command, and also don't benefit from mana tap/soul harvest. Is that the intended behavior?

A: Yes, Dimensional Rifts are effectively short-lived pets.