Here is the full list of all 26 Heart of Battle achievements.
Gain your first arena title.
Be the first to kill during a death fight.
Save an ally's life during a death fight.
Lead the rescue of trapped gladiators.
Gain fame, for good or ill.
Gain a reputation for associating with the rebels.
Be recognized for humiliating a disliked colleague.
Be recognized for sabotaging arena renovations.
Gain a reputation for reliable, steady work.
Share intimacy with the Duelist as quickly as you can.
Make the best impression at the Coastal Estate.
Begin your association with rebels in the best position.
Agree to an enemy's request.
Renege on a deal.
Get Velez to like you.
…You didn't need Velez to like you anyway.
Romance the Healer.
Romance the Glory Hound.
Romance the (Ex) Revolutionary.
Romance the Patron.
Set up the Glory Hound and the Revolutionary.
Officially romance at least two people at the same time.
Avoid a riot.
Incite a riot under your control.
Never lose a fight.
Let your rival live.