Like all other Beast weapons in Heroes; Lethe's weapon has multiple facets to it. The first part is a simple Speed boost. On top of that, as long as Lethe is alone, she gains Atk/Spd +6 during combat; an effect identical to Atk/Spd Solo 3. Finally, as with all cavalry beast units, Lethe gains Atk +2 and the combat initiation bonus of Atk/Def -4 on his opponent and blocks their follow-up attack.
Brazen Cat Fang
Grants Spd+3. If unit is not adjacent to an ally, grants Atk/Spd+6 during combat. At start of turn, if unit is adjacent to only beast or dragon allies or if unit is not adjacent to any ally, unit transforms (otherwise, unit reverts). If unit transforms, grants Atk+2, and if unit initiates combat, inflicts Atk/Def-4 on foe during combat and foe cannot make a follow-up attack.