Level 3
Fencer's Strike.
Roll one more Focused Strike die when you use it against a creature you . On crit, regain the Stamina expended for Focused Strike.
Let's Duel.
(1/round) Free action: a creature you can see (it loses this condition when you're , someone else it, or you another creature). While it has this condition, your attacks have Advantage against it.
Level 7
Just a Feint.
(1/turn) When you miss an attack, make another attack for free, dealing extra DEX damage and gain STR Stamina on hit.
Level 11
Fencer's Strike (2).
Upgrade the damage dice by 1 step (d4 → d6, d6 → d8).
Level 15
Keeping Tempo.
Gain 3 Tempo/Safe Rest. Consume to use one of: (1/turn) Free action: at the end of the turn, gain an additional action if you haven't missed an attack; (1/turn) Free reaction: make one attack miss (does not work on attacks that can't miss, like an AoE attack).