Actually it might save Belgarad if they make it to the top!!! Bel is a power rage he is set up for defensive warriors, its the quick fast rage/theatrics that kick his ass. Belgarad was designed to take on Laharl and Eruption, they where the top glads when he was made, so i found a slave with a huge natural str and Chi. 180 str/124 chi and a pair of heavy maces goes threw that heavy armor really well.
Delta, Wargh, Prey, Ormgar are the glads that i know if they attack belgarad i am 90% looking at a loss unless Bel gets lucky with a stun or a huge hit and jumps their last stand. But since those are speed demon's the guys you listed have a good chance to beat them, its all a nice circle of pain.