Deluge, Volcano, Violent Gale?

[Frogboy]

basically it just means that as long as the skill's duration isn't up you can bring your "ground buffs" anywhere on the same map with you, meaning you go to a geo's map, cast volcano, stand inside it, cast FB 10, kill the few geos around there, then tele to another part of the map, then recast volcano it will have no gem cost, just move the AoE to a new location, allowing you to continue usage of the skill.

and a 5 minute duration is a pretty long duration to have i think.