Guild Wars 2

Okay…first of all, I noticed this guy wielding a staff as a Dolyak. Then after that, he removed the staff, cast portal entre (a mesmer spell) and an elemental’s lightning spell while still in Dolyak form. Then he switched to a rifle. Now note, he’s a thief, apparently. Is this supposed to happen? Some kinda consumable that turns you into a Dolyak and gives you those skills?