Pathfinder 2 Combat Example

In this example, our protagonist, Seord Bordia a fighter with desert nomad background, encounters two Orc Brutes harassing some travelers at an oasis.

The two brutes are 30 feet away from Seord, both sides have their weapons drawn and are beyond the point where simple words will solve the issue.

Round 1 

Seord wins the initiative, and takes a Stride action to move forward 10' and throws a bola at an orc, using it for its tripping effect, this is an Athletics check vs the target's Reflex DC, in this case a 14.

Seord hits with a 16, which knocks one of the Orc's prone. Had he landed a critical success (10 over the DC/AC, she would also have inflicted 1d6 damage)

She takes another Stride action to move back 25'.
At this point she is 45' away, and only has her shield in hand, but not Raised.

This uses her three actions.

The Orc that was not knocked down uses two Stride actions to close the distance, and then attacks. The Orc hits with a total of 18, but Seord uses her Reactive Shield reaction to raise her AC to 20 for tis attack, so it is a miss.

The Orc that was on the ground uses an action to Stand, and two to Stride towards Seord.

Round 2

Seord uses an Action to ready her Scimitar and uses an action to attack the first Orc, hitting with a 25, which is also 10 over triggering a Critical (double damage with this weapons).
Seord's scimitar ends up hitting for 15, which is all of its Hitpoints. Orcs have a trait that keep them in the fight, so its HP total drops to 1 and it becomes Wounded 1. It will drop if it goes to wounded 3.
Seord uses her last action to strike again (-5 using the same action twice in a round) and hits again.
This drops the Orc to Wounded 2.

The wounded Orc and the unwounded Orc are flanking Seord, causing her to be Flatfooted (-2 circumstantial AC). The wounded Orc strikes at her with his knuckle daggers and gets a 16 vs her now modified AC of 16 which would hit, but Seord uses her Reaction to raise her shield, again bumping her AC up by 2 points and deflecting the blow.
He will use a second action to Strike her , and as her reaction is already used, she may not use Reactive Shield if he hits.
Luckily for her, the Orc rolls a modified 11, followed by a modified -2 which is a Critical Failure.

Critical Failures on attacks do not create an additional effect in combat, however some Creatures/Talents have specific Reaction attacks that trigger on Critical Failures from attackers.

The other Orc is going to attempt to Disarm Seord with his knuckle dagger (a feature of the weapon). This is an Athletics check vs Seord's Reflex DC of 16. The Orc succeeds, but not Critically, so Seord is at -2 to handling the weapon through her next turn, and all other attempts to Disarm her are at +2.
The Orc will then Strike her at -5 and at -10, the first hitting with a 16 (She cannot use her Reactive Shield) and inflicts 4 damage on her.

Round 3

Seord is going to bash the wounded Orc with her shield (her scimitar is off balance, and she only needs to hit him to take him out at this point). She gets a modified 18, which hits, and will do 1d4+4 damage, more than enough to take him out.
She will then take a Step back, and then Stride, putting 30' between her and the remaining orc.

The healthy Orc needs to Stride twice, and then attacks with his weapon, hitting her. She reactively raises her shield, and though not enough to stop the hit, can now use the Hardness value to absorb damage from the attack.

The Orc does 7 damage, 5 of which is blocked by the shield, and 2 of which hurts Seord and drops her shield'd Hardness to 3.

Seord is now down to 13 HP.

Round 4

Seord strikes twice, hitting once for 8 damage and then Raises her shield.

The Orc swing twice at her, hitting once and Seord blocks absorbing 3 damage, and she take 3. This is also enough damage for the shield to be destroyed.

Round 5

Seord attacks three times, the first hit dropping the Orc to 0 hitpoints, the Orc's ferocious trait keeping it at 1hp but going to Wounded 1.

The second hit takes the Orc to Wounded 2.

The third is a miss, but she spends a Hero Point to land it, killing the Orc.

At the end of the fight, Seord is down to 10HP, and her shield is destroyed.