Unidentified Mandalore

An Unknown Mandalore rose to power among the Mandalorian clans following the death of Mandalore the Ultimate at the Battle of Malachor V. Around the time of his capture in 3,957 BBY, Revan sent HK-47 to assassinate him; the droid failed. In 3,956 BBY he ordered a team of Mandalorians to Kashyyyk to test the effectiveness of new cloaking systems.

Apparently by 3,951 BBY he had been killed or deposed.