Hellgates

The Gates of Fire are a pair of relatively small warp rifts in the Segmentum Solar. They are however within 2000 light years of Holy Terra rendering them an acute threat to the safety of the Imperium.

Chaos Powers of Ashaklun
If you look steadily into the vortex of the Ashaklun Gate, which by the way is not at all advisable, you may catch a glimpse of the deceptively beautiful peacock hued surface of Ruhk, dominion of Xeraz the Exquisite, a Daemon Prince of Slaanesh. The roseate aura of warp-energies surrounding the gate enfold the systems under Xeraz's control.

Chaos Powers of Nebroel
The alternating sickly green or fire red energies constantly exploding from this gate reveal the constant internecine battle between the followers of Nurgle on the Daemon world of Lazar and the followers of Khorne on the daemon world of Kaleel.