There are at least 8 cutlass skills we don't have
but often used by enemies, they are:
(1) Double Cut
(2) Wild Swing
(3) Savage Blow
(4) Flurry
(5) Coupe De Grace
(6) Reposte
(7) Stab
(8) Lunge
Most are low to medium damage attacks.
Do you think they will be available to us as new cutlass skills?