Selected the Huns for Era 2 (classic) and Norse for Era 3 (medieval).

When the horsebowmen are embarked - they inherit the attack stats of the cultural unique Langskip transport, but retain their original double-attack ability. The result is rather amazing (and unbalanced) - double ranged attack with strenght 36 (33 from Langskip, but +3 from Huns cavalry bonus...). The original horsebowmen had a much lower strength attack (22 base) to balance out the power of the double action ranged ability.