Prime ability: Strength; the Fighter core class, and its subclasses, enjoy the best hit die available to PCs, the mighty d8. Additionally, the Fighter and its subclasses gain a +1 to Attack Bonus every single level. The Fighter core class (not its subclasses) gains a bonus HP at every level — this is in addition to the normal gained for level increase and Constitution bonus.

Party Boon at Fighter 1: Once daily when you join one or more adventuring party members as a combat ally, you may choose one ally. As long as you fight side-by-side or back-to-back with that ally, the ally enjoys an AC bonus of 4 points for the duration of the combat encounter.

Personal Boon at Fighter 3: When you are reduced to 0 HP or lower, make both a Strength and a Constitution check. If you succeed at only one or the other, regain 10 hit points. But if you succeed at both, regain 20. You may use this extraordinary ability a number of times per long rest equal to your Strength modifier, or once — whichever is greater.