The Homecoming Wiki needs to be updated. Someone edited it to add the "Vulnerability" inherent power, but accidentally deleted "Opportunity" from the inherent power section.
https://homecoming.wiki/wiki/Sentinel
https://homecoming.wiki/wiki/Opportunity
They must have misunderstood the patch notes. Sentinels now have two inherent powers, "Opportunity" and "Vulnerability".
Changes to Sentinel Inherent:
Sentinels have an inherent resistance to Perception and ToHit debuffs (10%).
* Opportunity builds automatically at a rate of 100% per minute.
* Sentinels now have an inherent power called Vulnerability:
* Vulnerability consumes 50% of your Opportunity to debuff a single target for 15 seconds.
* Vulnerability is Auto-Hit and ignores level differences.
* Vulnerability debuffs the following:
* Damage Resistance
* Defense
* Mez Resistance
* Stealth
* Resistance to Endurance, Endurance Discount, Recovery, Regeneration, ToHit, and Recharge
* Removed old Opportunity Debuff Effects/Modes from T1/T2 powers.
* Removed old Inherent Proc.
* Removed old Offensive/Defensive Opportunity Modes.