Combat Mechanics

Agility Class (AC)
Agility class is a characters ability to not get hit, referring both to the act of voiding and blocking. AC is a passive score which an enemy must roll above in order to hit, given by this formulae

10 + Dexterity Mod

In addition, AC can be gained by various other factors and equiptment

- Wielding a Melee Weapon grants +1 AC

- Wielding a shield grants AC based on the size of the shield

- Some spells or magic items

Deadlock
Most creatures can fight only one opponent at a time and will suffer penalties if attacked by multiple opponents. When two opponents engage, they enter a deadlock, where they are focused on fighting each-other. If a creature in a deadlock is attacked by a second opponent, they are said to be overwhelmed and receive a -2 penalty to AC and an additional -1 penalty for each creature attacking them. So, a soldier attacked by two wolves would receive a total of -4 to their AC, and an additional -1 AC for each wolf after that.

It is important to note that once the deadlock limit is surpassed, all enemies count for calculating the penalty. Say a soldier with Multi-deadlock was being attacked by wolves. His Deadlock Limit is 2, so they can fight two wolves with zero penalties (Unlike the soldier above). However, if a third wolf attacks them, they suffer the full penalty: -2 AC for being overwhelmed, and +1 for each of the three wolves - A total of -5 AC.

Now Imagine a ranger with 20 AC and Heroic multi-deadlock. Their Deadlock Limit would be+6, so they could fight 6 enemies at once without suffering penalties. However, once a 7th enemy joins in they would suffer the full penalties: -2 AC for being overwhelmed, and an additonal -1 for each enemy for a total of -9 AC.

Some creatures have multi-deadlock abilities, allowing them to enter deadlock with multiple enemies before taking a penalty. Medium and Smaller creatures have a base deadlock Limit of 1, but Large and above creatures have a base deadlock limit of +1 for each increasing size category, in addition to possible abilities.

Ranged attackers do not trigger a deadlock, nor do they count for becoming overwhelmed: A soldier attacked by 10 goblin archers suffers no penalties to AC, but a soldier attacked by 10 goblin archers and two goblin spearmen suffers -4 AC from becoming overwhelmed with the spearmen. Since this is a penalty to the defender rather than a bonus to the attacker, the 10 goblin archers are able to make use of this lowered AC.

A character that is surrounded - all 8 adjacent squares are occupied by an opponent - suffer an additional -2 to their AC. This means a surrounded character suffers a total -12 penalty to AC when surrounded, unless their deadlock limit is 8 (This is possible as a large creature with heroic-multi deadlock, 20 dex, and a sheild, or a medium creature with heroic-multi deadlock, 30 dex, and a sheild,or with magic items that improve deadlock).

There are ways to improve deadlock limit.
A dex of 20, and every 10 after that, increases the deadlock by 1.

A large sheild improves deadlock limit by +1 (Ie, Sheilds larger than a Buckler), in addition to improving AC.

Some magic items may imrpove deadlock limit.

There are also three new feats that can be taken that improve deadlock;
 * Multi-Deadlock: You can fight one additional enemy before suffering penalties (+1), Requires 13 Dex.
 * Improved Multi-Deadlock: You can fight one additonal enemy before suffering Penalties (+1), Requires 15 dex. Stacks with Multi-Deadlock.
 * Heroic Multi-Deadlock: You can fight two additional enemies before suffering penalties (+2), Requires 17 dex. Stacks with Multi-deadlock and imrpoved multi-deadlock.

Avoiding becoming Overwhelmed
Because the grid is square, the maximum adjacent enemies is 8. However, this can be limited with positioning: A tree or rock may protect a flank, as may a tanky comrade and phalanx formation.

Critical Hits
Players rolling naturally within their critical threat range make a critical hit, where their weapon finds it way into a weakness of armour or other weakness to deal massive damage. Rather than a multiplication, critical hits automatically deal full damage (ie, a weapon with dealing 1d8 damage will automatically deal 8) and ignore armour.

In addition, if you take more than 80% of an opponents full (not current) health in a single crit, you strike a mortal blow (Reduce HP to 0 and bleeding out)

Some weapons in D&D 3.5 have different critical modifiers. In this system, these modifiers change the amount of health needed to perform a killing blow, As below;

Weapons with x2 crits - 80% full health in a single hit.

weapons with x3 crits - 65% full health in a single hit.

Weapons with x4 crits - 50% full health in a single hit.