XCOM damage:

- Conventional weapon damage is reduced by 1
- Magnetic and beam weapon damage is reduced by 2
- Damage of all swords and pistols is reduced by 1
- Tier 3 pistol damage spread is made equal to other pistols
- Crit chance is reduced to 10 for all shotguns
- Crit chance is rescaled to 10/20/30 for tier 1/2/3 sword
- Bonus damage on crit for most of the XCOM weapons is made equal to 33% of base damage (rounded): weapons with 1,2,3,4 base damage deal +1 dmg on crit, weapons with 5,6,7 base damage deal +2 dmg on crit, etc
- Frag grenade damage is reduced by 1. Plasma grenade damage is unchanged
- Damage of fire and poison debuff grenades is set to be slightly higher then that of standard counterparts, armor shred is removed. Acid Grenade/Bomb damage and shred are reduced. Units that are immune to said effects will not suffer any damage from these grenades
- Proximity Mine damage is reduced to 5
- Heavy weapon damage is significantly reduced
- Blaster Launcher shred is reduced to 2, Shredstorm Cannon shred is reduced to 3
- Plasma Blaster armor pierce is reduced to 3, armor shred is increased to 3
- Tier 3 Psi-Amp abilities are set to deal about as much damage as old tier 1 Amp ones. Tier 1 and 2 Amp abilities deal even less damage
- Combat Protocol damage against robotic units is reduced
- Capacitor Discharge damage against both organic and robotic units is reduced
- Alien Hunters DLC weapons are set to be somewhat closer to their vanilla counterparts in terms of power (but are still better in most cases)
- Crit chance is reduced to 0 for all axes
- Damage of weapons obtained by killing the Chosen significantly reduced, some of the effects are weakened

Items:

- Values for percentage based weapon addons are reduced from +5/+10/+15 to +4/+8/+12
- Repeaters are reworked to increase critical damage of all primary weapon shots (+1/+2/+3 for tier 1/2/3)
- Laser Sight maximum close range crit bonus is is reduced and drops off faster at longer ranges
- Smoke Grenade/Bomb defense bonus is increased to 25. Smoke Grenades are made more reliable in general
- Smoke Grenade/Bomb radius is increased by 1
- Bluescreen Rounds bonus damage is reduced to 2, Hack Defense reduction is set to 30
- Hack Defense reduction of EMP Grenade/Bomb is set to 30
- Similar Hack Defense changing effects do not stack and can not overwrite each other
- Armor penetration of AP Rounds is reduced to 3
- Bonus damage of Dragon, Venom and Talon Rounds is set to 0
- Talon Rounds crit chance is increased by 5
- New experimental ammo type: Needle Rounds. (Deal +1 damage to all targets)
- All tier 2 armor HP bonuses are set to 4
- Nanofiber Vest HP bonus is increased to 2
- Hellweave HP bonus is reduced to 1
- Passive bonuses to aim and crit chance are added to Overdrive Serum
- New item: Stealth Suit (gives +15 dodge and reduces Detection Radii of enemy units by 50%, unlocked when Faceless Autopsy and Hybrid Materials are researched)
- New item: Alloy Vest (gives +3 HP and +1 mobility, unlocked when Powered Armor is researched)
- Skulljack hack bonus is reduced to 20
- Tier 2 Gremlin hack bonus is reduced to 15, tier 3 bonus is reduced to 30
- Tier 2 Psi Amp psi offence bonus is reduced to 10, tier 3 bonus is reduced to 20
- Radius of Flamethrower and Hellfire Projector is increased, range is slightly reduced. Both weapons are set to apply burning effect to their targets
- Descriptions of heavy weapons are updated to display more clear stats: weapons with conic areas of effect display length and max width in tiles, all heavy weapons also display armor shred and pierce if there is any
- Armors from Alien Hunters DLC are 50% less likely to cause panic among specific aliens
- HP bonus is reduced by 1 for all Alien Hunters DLC armors
- Rage Strike damage is reduced, armor shred is set to 0
- Freezing Lash min Ruler freeze duration is reduced to 1. (Max duration is 2 as in vanilla)
- HP bonus of tier 2 and 3 SPARK armors is significantly increased
- Increased SPARK Cannon clip size by 1 for tier 2 and 2 for tier 3 weapons, added +5 aim bonus and +10 crit chance bonus to tier 2 and tier 3 cannons respectively. Weapon upgrade slots are removed

Abilities:

- Units with Shredder perk are set to destroy 1/1/2 armor on hit with conventional/magnetic/beam weapons
- Blast Padding damage reduction is increased to 75%
- Volatile Mix bonus damage is reduced to 1
- Chainshot aim penalty is reduced to 10
- Rapture ability is no longer guaranteed to deal critical damage
- Biggest Booms crit chance is increased to 30%, bonus damage is reduced to 1
- Number of Combat Protocol charges is reduced by 1
- Shadowstrike aim and crit chance bonuses are reduced to 20
- Reaper cooldown is reduced by 1
- Rapidfire aim penalty is increased to 20, cooldown is reduced to 1 (can only be used once per turn)
- Hunter's Instinct bonus damage is reduced to 1, bonus crit chance is reduced to 5
- Deadeye ability is reworked: fires a shot that always deals critical damage
- Bonus accuracy from Sharpshooter's Aim ability is reduced to 15
- Stasis cooldown is increased by 2
- Soul Steal is changed to recover 1 HP for each point of damage dealt
- Overdrive recoil penalty is increased to 20
- Rainmaker bonus damage is reduced to 1
- Strike cooldown is increased by 2, aim bonus is reduced to 5, damage is reduced, armor shred is added
- Success chance of Intimidate is increased for tier 1 and reduced for tier 3
- Repair HP per use is reduced to 3, number of charges is set to 3
- Damage of Bombard and Nova abilities is reduced
- Sacrifice ability is reworked: 1-time use per mission as a free action, permanently adds +4 armor, but reduces defense by 30
- Shadow mode's mobility boost is increased to 50%, base mobility of Reapers is reduced to 8
- Remote Start explosion no longer deals extra damage. Cooldown is significantly increased
- Soul Harvest crit chance increase per kill is increased to 10
- Sharpshooter's Aim ability is added to XCOM perk pool of Skirmishers and Reapers
- Void Conduit can no longer be used against enemies that are immune to mental attacks, but can now be used on humanoid aliens

Hunker Down rework:

- Works outside of cover
- Costs 1 action point and does not end the turn (soldiers may fire their weapons, use abilities, etc. like they usually do), but makes them unable to move for the rest of it
- Defense bonus is reduced to 25
- Still puts out the fire as in vanilla

Weapon range:

- Shotguns gain extreme aim boosts at close range, but their accuracy quickly fades away at longer ranges
- Rifles and cannons gain increased aim bonus at point-blank ranges. (Rookies have 100 aim vs adjacent enemies without innate defense)
- Pistol weapon range is changed to medium. Shadowkeeper is unchanged
- Range penalty of sniper rifles is increased. Squadsight aim penalty is unchanged
- Shadowkeeper aim bonus is increased to 20
- Most of the enemies are set to have a minor close range aim bonus. Some special units have different bonuses and penalties
- Added sniper rifle range penalty to Reaper weapons

Missions:

- Final mission enemy compositions are completely reworked and feature multiple unique enemies and bosses
- Fight against rapid-moving Subject Nefas, fearsome Sectopod Mark 2 that can eat ABA Primes for breakfast and mysterious "true boss" - Master, who can singlehandedly destroy your squad unless approached carefully
- Gatecrasher pod compositions are reworked and include three new boss units (each boss has unique set of enemy pods, allowing players to find out which one has spawned and prepare for the encounter)
- Turn limit is increased for most of the timed missions
- Wave limit is added to all missions with The Lost and The Horde sitreps
- The amount of containers on Supply Extraction and health values of armed civilians on dlc Retaliation are increased. The minimum amount of saved civilians required to win basic Retaliation is reduced
- Pod compositions on tutorial recovery mission are reworked
- Hack Defense of the Lost Towers' final enemy is increased on Commander and Legend difficulty levels

EXALT:

- New set of enemy units is added into the game. Features two tiers that appear in early- and late-game stages of the campaign
- Tier 1 EXALT: Advisor and Heavy - leaders; Volunteer, Assault, Apprentice, Bladerunner and Marauder - followers
- Tier 2 EXALT: Elite Sniper and Elite Captain - leaders; Elite Assault, Elite Marksman, Elite Bladerunner, Elite Shieldbearer - followers
- All tier 2 EXALT units spawn at force levels 19+ and have massively higher chances to appear compared to ADVENT units (which may still spawn from time to time)
- Three bosses (Sniper, Commando and Captain) with individual supporting pod compositions are added to Gatecrasher and Blacksite missions. Gatecrasher ones drop random tier 2 weapon upgrade upon death

New units:

- New Lost type: Wild Chryssalids. May appear as Lost pod leaders and (later) followers, do not have poison, but can attack after dashing, deal relatively high damage and pierce 1 armor
- New alien type: Heavy Muton - late-game version of regular Muton
- New alien type: Centurion - an improved late-game melee focused version of Archon

Strategy level:

- New resource is added: Equipment Fragments (dropped by all EXALT units)
- Hybrid Materials and Predator Armor schematic corpse requirement is replaced with Equipment Fragments cost. Equipment Fragments cost is also added to Plated Armor research, EXO Suit and Spider Suit
- Chryssalid Autopsy completion time is significantly reduced
- Plasma Rifle research project is renamed into "Plasma Weapons" (because why not?)
- Maximum number of faction heroes to recruit is increased to 3 for all factions.

Vanilla Enemies:

- Supression aim penalty of all enemies that have this ability is increased to 50
- Enemy units' decision to use Overwatch is no longer affected by the presence of evac point
- Absorption Plating ability is added to Sectopods, Prototype Sectopods and Heavy MECs
- Frag Grenades are replaced with Stun Grenades on all Officers. Stun grenades deal minimal amount of damage and apply stun effect to all targets in the area
- HP of tier 1 ADVENT Trooper is increased to 6, grenade with small radius is added to loadout. Begins to spawn at the same time as basic Stun Lancer
- HP and aim of ADVENT Stun Lancer (basic one) are reduced across all difficulty levels
- One armor is added to tier 3 ADVENT Trooper on Legend difficulty level
- Grenade armor shred of tier 3 ADVENT Trooper and Muton is increased from 1 to 2
- Hack Defense of Sectopod is increased by 10
- Cooldown of Wrath Cannon is reduced by 1, damage and shred are significantly increased for all types of Sectopods. Wrath Cannon is set to end the turn after being used
- Armor shred of Heavy Turret and Superheavy Turret is increased to 1. Damage of Heavy Turret is reduced by 1
- All turrets are set to enter Overwatch after XCOM engages in combat even if they are not revealed yet
- Armor shred of Heavy MEC's Micro-Missiles is increased to 2
- Aim of ADVENT Stun Lancer and Archon is reduced by 5
- Primary weapon of ADVENT Shieldbearers is changed to Mag Repeater (looks cooler and shreds armor)
- Primary weapon of Heavy and Elite Lancers is changed to Mag Shotgun
- Defense of ADVENT General is reduced across all difficulty levels
- Base damage of Archon is reduced to 6-8, melee attack damage is increased to 7-9
- Range of Viper's Tongue Pull ability is reduced to 2-7 tiles
- +1 damage chance of Viper's Bind ability (to deal 3 damage instead of 2) is increased to 50%
- Damage of Viper, Codex and both Spectres is set to 4-6
- Damage of Muton is increased to 5-6
- Melee attack armor shred of Berserker is increased to 1
- Melee attack armor shred of Andromedon is increased to 2
- Damage of Gatekeeper is increased. Damage type of the main weapon is changed from Explosion to Beam (same as for other aliens)
- Health of Gatekeeper is increased by 5. Armor bonus from Closed Shell is increased by 1
- Will of Gatekeeper is increased by 30 on Legend and Commander and by 10 on other difficulty levels. Aim is increased by 20/10 respectively
- Bonus armor and dodge are added to Chryssalids
- Base crit chance of Avatar is increased by 5
- Viper King's weapon is set to have additional 25% chance to deal +1 damage
- Neonate Viper's flanking crit chance is set to 33 on Rookie and Veteran and to 40 on Commander and Legend
- Alien rulers begin to appear slightly later than in vanilla (if DLC is disabled)
- One point of Derelict MEC armor is replaced with +1 HP across all difficulty levels
- Base damage of Flamethrower is set to 1-2 for all tiers of Purifiers
- Late-game weapon damage of Chosen enemies is increased
- Lost units are reworked and feature 4 tiers of units with increasing stats and damage. Dodge is added to Dashers, Armor Chance is added to late-game Brutes

Overall difficulty and misc changes:

- Easy to hit mod (negative defense) of civilians on retaliation and council missions is reduced from 35 to 0
- High cover defense is increased to 45. Low cover defense is increased to 30
- Max amount of engaged enemies is set to 99 on Comander and Veteran, and to 5 on Rookie difficulty level
- Aim assists are removed from all difficulties
- Defense of SPARKs is reduced to 10, base armor is increased by 1, aim is increased by 5
- Defense of Reaper soldiers is reduced by 5