Baeldun was instrumental in defeating Shiver's forces at White Falls. He and the 7th Legion fell on her rear guard and destroyed it utterly. Then, the combined forces of Alric and Baeldun defeated Shiver's army. A week later Shiver returned with an army of Myrkridia and beat back the forces of Light. Tandem's fall was inevitable.
It is uncertain of the powers that Baeldun held. Some say he is the son of Maeldun (given that their names are quite similar). If this is so, he probably had powers closely related to concussion and energy--fan made plugins show him to be more paladin like, with the ability to create a Healing Burst (a healing blast that effects all in a large radius).