You can transform your eldritch blast into a malevolent curse that lingers over a creature. An eldritch curse does not require an attack roll. Instead, the target is afflicted by a curse that lasts for 1 minute or until discharged. A creature cursed this way is considered flat-footed: it is denied its Dexterity bonus to AC, and it cannot make attacks of opportunity or take immediate actions. The next time the target is struck by a successful attack roll, whether your own or another character's, the curse is discharged and the target is affected as if by your eldritch blast, including any eldritch essence you applied as you cast the eldritch curse. Multiple castings of eldritch curse stack. An eldritch curse always creates a conspicuous omen portending the target's imminent doom. This sign resembles the normal visual manifestation of your eldritch blast, including any eldritch essence used, in a cloud or halo around the target. For example, a vitriolic curse might appear as a greenish vapor, while a brimstone curse could be a ring of flame around the target's head. The sign imposes a -2 circumstance penalty on the target's Hide checks, and anyone observing it gains a +4 bonus on Spellcraft checks to identify the curse's effect.