Striker

In addition to being a combat role, Striker is a Spheres of Might class. Not the most imaginative name, but it describes them pretty well: they hit things.

Strikers focus on lightly armored unarmed combat like monks thanks to innate access to the Boxing, Brute, and Open Hand spheres, but unlike monks their fighting style is usually less "wise kung-fu master" and more "twitchy adrenaline junkie". They have a combat resource called Tension that is gained over the course of battle and then used to gain bonuses such as bonus damage, free movement, temporary hit points and rerolls for saving throws.

The access to archetypes can significantly change how Strikers operate, though they still tend to rely on smacking foes around.

• Barfighter replaces the dependency on punching to a dependency on booze. Fortunately, they develop quite a resistance to hangovers.
• Blackpowder Brawler makes guns the preferred weapon, particularly pistols so you can still punch or chop while in close quarters.
• Shadowed Fist pretty much turns them into SoP Ninjas, complete with the ability to spend tension for ki.
• Strong Style Grappler makes the class dependent on the Wrestling sphere for grappling tricks and throws.

5E

With the transition to 5E, the port of the Striker hasn't seen quite a significant change to their premise. Even better is the fact that they aren't at all dependent on any single fighting style, as not only is the Boxing sphere here relabeled as the Retribution sphere, it also loses all dependency on punching to get everything to work. This also means that the class is entirely dependent on Tension to operate, though some subclasses add more use to the resource.

• Boxer gives us the closest to the original Striker by granting punches as good as a monk's as well as the exceptional proficiency on ALL SAVES.
• Bloodriser gives a discount version of the Bloodrager by using tension to cast spells.
• Skirmishing Scout isn't very combative, but it gains the Scout sphere as well as some extra evasive trickery.

The Third Party Classes of Pathfinder
Psionics:	Psion - Psychic Warrior - Soulknife - Wilder Aegis - Cryptic - Dread - Marksman - Tactician - Vitalist
Path of War:	Stalker - Warder - Warlord - Harbinger - Mystic - Zealot
Akashic Mysteries:	Daevic - Eclipse - Guru - Nexus - Radiant - Rajah - Stormbound - Vizier - Zodiac
Spheres of Power:	Armorist - Elementalist - Eliciter - Fey Adept - Hedgewitch - Incanter Mageknight - Shifter - Soul Weaver - Symbiat - Thaumaturge - Wraith
Spheres of Might:	Armiger - Blacksmith - Commander - Conscript Savant - Scholar - Sentinel - Striker - Technician
Spheres of Guile:	Agent - Courser - Envoy - Mastermind - Professional
Champions of the Spheres:	Prodigy - Sage - Troubadour - Dragoon - Mountebank - Necros - Reaper Warden - Crimson Dancer
Pact Magic:	Pactmaker (formerly known as Medium)