Gain Phasing for 4 seconds on Kill
You have Phasing while at maximum Frenzy Charges
You have Phasing during Onslaught 
Quartz Infusion is a notable Ascendancy passive skill for the Raider. It grants additional chance to dodge attacks, and grants the Phasing buff on kill. It also causes you to gain Phasing while you have the Onslaught buff or at maximum frenzy charges. Phasing's visual effects and buff icon will not show while at maximum frenzy charges but phasing will anyway be active.