If you weren't asking about RuneScape, it might be a typo or a specific regional variation of:

In the context of gaming (specifically ), "isbarrar" is a Swedish slang term derived from the spell Ice Barrage .

It is commonly used by Swedish players to describe the act of casting that specific spell, often during PvP (Player vs Player) combat or minigames like Castle Wars. For example, a player might say they are "isbarrar varandra" (ice barraging each other) to describe a long magic fight.

(Aragonese): To go off track, deviate, or lose one's way.