Coalesce is a client or server-side, fully configurable mod that overhauls some aspects of combat, introducing a more realistic version of combat without completely changing the game.

Changes:

Max Heal: Whenever a player takes damage, a portion of that damage reduces their "Max Heal". Players cannot regenerate beyond their Max Heal. Max Heal takes armor into account when a player is damaged, but damage types tagged in "forge:coalesce_ignore_armor" will bypass this. There are three ways of restoring Max Heal: Sleeping, Potions, Death.
When a player wakes up from sleeping, their regain some Max Heal (default: 1) up to a certain percentage (default: 75).
Having Regeneration/Instant Health or any source of healing granting more than 1 HP at a time will increase Max Heal by percentage (default: 20% of healing will also regen Max Heal, except for Regeneration which is automatically reduced by an additional 80%).
Dying will automatically reset a player's Max Heal to their Max Health.
Distance Damage: Damage now scales with distance - the closer you are to an enemy, the more damage you deal. Correspondingly, being farther away from an enemy reduces your damage. This only applies to damage types tagged in "forge:coalesce_melee"
Saturation & Food Negation: Coalesce overrides vanilla saturation (default: true) by setting its value to a player variable then setting it to 0. While the saturation variable is bigger than 0, the player will not lose food bars (like in vanilla). This results in the player's inability to regenerate several hearts from eating a single food item (such as a steak). Your saturation drains naturally even when standing still (default: 0.01 per tick) and will scale with your health (the lower health you are, the hungrier you'll be). Saturation can be affected by Hunger and Saturation potions (default: true).
Adrenaline: Upon attacking (x2 multiplier by default) or being attacked (x1 multiplier by default), a player is rewarded with "adrenaline" - increasing movement speed, attack speed and knockback resistance. Adrenaline fades over time, but the player can continuously stack the duration. When attacking with adrenaline, the player is given iframes as a reward - scaling with both adrenaline and damage dealt with the attack.
i-Frame Overhaul: Mobs are no longer granted iframes from damage type tagged in "minecraft:is_projectile" or "forge:coalesce_melee". In their place is a new system for iframes in which the target receives less damage instead. This encourages spam attacks for combo-breaking or creating space between you and your opponent, while enforcing the wait for maximal damage on both the weapon charge and iframe duration.

The mod can be configured through the file "coalesce_config.toml" found in the config folder.