The arcanist can alter an existing spell effect by expending 1 point from her arcane reservoir. To use this ability, she must be adjacent to the spell effect (or the effect’s target) and be aware of the effect. She can choose to increase or decrease the remaining duration of the spell by 50%. This ability can be used on unwilling targets, but the arcanist must succeed at a melee touch attack, and the target may attempt a Will saving throw to negate the effect. This ability cannot be used on a given spell effect more than once. This ability has no effect on spells that are instantaneous or have a duration of permanent.
Pathfinder Roleplaying Game Advanced Class Guide © 2014, Paizo Inc.; Authors: Dennis Baker, Ross Byers, Jesse Benner, Savannah Broadway, Jason Bulmahn, Jim Groves, Tim Hitchcock, Tracy Hurley, Jonathan H. Keith, Will McCardell, Dale C. McCoy, Jr., Tom Phillips, Stephen Radney-MacFarland, Thomas M. Reid, Sean K Reynolds, Tork Shaw, Owen K.C. Stephens, and Russ Taylor.