Invoke the Eye
Invoke the Eye is an effect that is commonly seen on "Men of Mordor" who are powerful black Númenoreans, the most powerful servants of the Dark Lord. By invoking the Eye, they receive a powerful buff from their master. One such example is Balhest, the final boss of Ost Elendil, who calls upon this power when he enters battle.
This effect is used by the following "Men of Mordor":