Combat overview

How the UO-style combat system works: hit chance, damage calculation, defense, health, and stamina.

The Skills plugin replaces vanilla combat with a UO-inspired system built around weapon skills, supporting skills, and an internal health pool that runs parallel to vanilla hearts.

Combat flow

1. Attack occurs

   A player swings a weapon or fires a projectile.

2. Hit chance check

   The system rolls against the hit chance formula. On a miss, no damage is dealt but the weapon skill still receives a gain check.

3. Damage calculation

   Base weapon damage is multiplied by Tactics, Anatomy, Wrestling (unarmed only), STR, quality, and DI enchant modifiers.

4. Defense applied

   Parry is checked first (chance-based, 50% damage reduction on success). Then armor rating (AR) reduces the remaining damage.

5. Final damage applied

   The result is applied to the target’s internal HP. The player’s vanilla hearts are synced to reflect the new internal HP percentage.

Hit chance

Hit chance is calculated using the attacker’s weapon skill against the target’s defense value.

Hit Chance = Weapon Skill − (Target Defense / 2) + 50
Minimum: 5% | Maximum: 95%

• vs. Mob: Target Defense = mob’s physical_defense from config
• vs. Player: Target Defense = the opponent’s Parrying skill

Weapon skill	Target defense	Hit chance
50	0	95% (cap)
50	50	75%
100	100	95% (cap)
30	80	40%

Parry

Parrying is a chance-based block that reduces damage on success. It triggers before AR is applied.

Parry chance (melee)

Equipment	Parry chance	Maximum
Shield (off-hand)	Parrying × 0.7%	70%
Weapon only	Parrying × 0.4%	40%
Bare hands	0%	—

Parry chance (projectiles)

Equipment	Parry chance	Maximum
Shield (off-hand)	Parrying × 0.8%	80%
Weapon / bare hands	0%	—

Arrows and bolts can only be blocked with a shield — weapon parry does not apply to projectiles.

Parry damage reduction

When a parry succeeds, the reduction scales with skill level:

Parry Reduction = 30% + (Parrying × 0.4%)
Range: 30% (skill 0) → 70% (skill 100)

Role in PvP hit chance

Parrying also raises the effective defense used in the hit chance formula:

Hit Chance vs Player = Weapon Skill − (Parrying / 2) + 50

Internal health system

The plugin manages an internal HP value that maps onto vanilla hearts:

Max HP = 100 + STR
Range: 100 (STR 0) to 200 (STR 100)

Vanilla hearts always reflect the internal HP percentage — they do not represent fixed half-heart increments.

Damage conversion

Internal Damage = Vanilla Damage × 10

After all skill and defense modifiers are applied, the final internal damage is subtracted from internal HP, and vanilla health is resynced:

Vanilla HP = (Internal HP / Max Internal HP) × 20

HP recovery

Source	Behavior
Food / natural regen	Standard vanilla behavior
Regeneration effect (golden apple, potion)	Internal HP += regen amount × 10
Heal / Greater Heal spells	Internal HP += spell heal amount × 10

STR, DEX, and INT effects on combat

Stats are derived automatically from the average of all skills that contribute to each stat. They cap at 100.

Stat	Combat effects
STR	Max HP +STR (100–200 total); mining/lumber speed bonus
DEX	Attack speed +(DEX / 2)%; movement speed +(DEX / 10)%
INT	Mana cost −(INT / 2)%; cast success rate +(INT / 5)%

Wearing heavy armor applies a DEX penalty that reduces effective DEX. Full Netherite armor costs 29 DEX, which directly reduces attack speed and movement speed.

Stamina system

Stamina is separate from HP and mana. It is consumed by sprinting and recovers at rest.

Max Stamina = 100 + DEX + (Focus / 2)

With DEX 100 and Focus 100, maximum stamina is 250.

Action	Rate
Sprint consumption	1 per tick (20/sec)
Rest recovery	2 per tick (40/sec)
Focus bonus consumption	× (1 − Focus / 200)
Focus bonus recovery	× (1 + Focus / 100)

Exhaustion state

When stamina reaches 0, the player enters an exhausted state:

• Walk speed reduced by 50%
• Jumping disabled
• Panting particle and sound effect plays every 0.5 seconds
• Normal movement resumes only after stamina recovers to 50

Focus bonuses are ignored during the exhausted recovery period — recovery is fixed at 2/tick until the 50-stamina threshold is crossed.

Related pages

Weapons

Weapon-skill table, full damage formula, archery specifics, and DI enchant reference.

Armor

AR system, full armor table, enchantment AR bonuses, and quality modifiers.