Jul 13, 2026
View on Steam↗HOI IV - Open Beta SE™ Update 1
3/5 Moderate
BETASubdoctrine mastery retention introduced alongside major balance overhauls for Self-Propelled Artillery, Tank Destroyers, and land unit experience.
Key Changes
- 1Experimental 25% mastery retention when switching Subdoctrines
- 2Significant nerfs to Self-Propelled Artillery and Tank Destroyer stats and tech progression
- 3Land unit experience combat bonuses reduced across all levels
- 4Armored Car production costs reduced to improve viability
- 5Naval AI now retreats for repairs at 75% strength (up from 65%)
- 6Infiltration Tactics doctrine received significant buffs to planning and Command Power
- 7Amphibious Tanks now restricted from using oversized guns
- 8Secondary Turrets on tanks now impose Soft and Hard Attack penalties
- 9Helicopter Logistics supply reduction significantly buffed to -60% at max level
- 10Naval doctrines rebalanced with nerfs to Torpedoes and buffs to Hunter Killer Groups
All Changes
🎮Gameplay(4)
- newSubdoctrines: When switching Subdoctrines, players now retain 25% of invested mastery into the new Subdoctrine.
- fixAmphibious Tanks: Superstructures now prevent mounting guns one category larger on Amphibious Tanks (e.g., Light Amphibious Tanks cannot mount Medium Cannons).
- fixBattalion Adjusters: Battalion Adjusters now scale based on the equipment and manpower status of the sub-unit.
- changeEssential Equipment Blocks: Added Essential Equipment Blocks for units including Heavy Weapons Company, Flame Tanks, and various Staff units to ensure proper stat scaling.
⚔️Land Balance(11)
- nerfLand Units: Combat bonus from experience reduced: Green (-15%), Trained (0%), Regular (+15%), Seasoned (+30%), and Veterans (+45%).
- buffSelf-Propelled Artillery: Self-Propelled Artillery combat width reverted to 2.
- nerfSelf-Propelled Artillery: Self-Propelled Artillery Soft Attack bonus reduced from +15% to +5% and Hard Attack reduced by 10%.
- nerfTank Destroyers: Tank Destroyers piercing bonus reduced from 15% to 5% and Soft Attack reduced by 10%.
- nerfSecondary Turret HMG: Secondary Turret HMG now applies a -4% Soft Attack penalty.
- nerfSecondary Turret Small Cannon: Secondary Turret Small Cannon now applies a -5% Soft Attack and -5% Hard Attack penalty.
- buffHeavy Howitzer: Breakthrough penalty on Heavy Howitzer and Rocket Launchers reduced from -4 to -2.
- buffArmored Car: Armored Car equipment cost reduced across all tiers (e.g., Tier 1 reduced from 3.5 to 3 IC).
- buffHelicopter Logistics Company: Helicopter Logistics Company base supply reduction and tech bonuses increased to -15% each (max -60%).
- nerfEngineers: Flame Tank and Assault Engineer attack bonuses in Urban terrain reduced by 5%.
- buffExperimental Facilities: Experimental Facilities now benefit from Infrastructure construction speed bonuses.
📜Land Doctrines(5)
- buffInfiltration Tactics: Infiltration Tactics adoption planning bonus increased from +5% to +10%.
- buffInfiltration Tactics: Infiltration Tactics 3 daily Command Power bonus increased from +0.01 to +0.1.
- changeDesperate Defense: Desperate Defense can now be adopted if a country has 10% Surrender Progress and 50% War Support.
- buffFlying Batteries: Flying Batteries 1 now grants +5% Soft Attack and +10% Breakthrough.
- buffFlying Batteries: Flying Batteries 5 now grants +5% Soft Attack and +10% Defense.
⚓Naval Doctrines(4)
- changeAnti-Aircraft Cruiser: Anti-Aircraft Cruiser adoption Naval AA bonus reduced from +20% to +10%, but added +10% Armor for Heavy Cruisers.
- nerfTorpedo Primacy: Torpedo Primacy bonuses for Torpedo Attack, Depth Charges, and Sub Detection reduced across multiple rewards.
- buffHunter Killer Groups: Hunter Killer Groups bonuses for Sub Detection and Depth Charges increased to 20%.
- nerfPatrol Boats: Patrol Boats 2 Torpedo Attack bonus reduced to +10%.
🤖AI(1)
- changeNaval AI: AI fleet repair threshold increased from 65% to 75% strength ratio to improve fleet longevity.
🐞Bug Fixes(2)
- fixLight Tank Destroyer: Light Tank Destroyer Regimental Support now correctly applies the Soft Attack penalty.
- fixArmored Engineers: Armored Engineers now provide 5%+ Breakthrough instead of 0.05.
Summary
Experimental Systems
This first update for the Open Beta SE™ introduces an experimental mechanic allowing players to retain 25% of invested mastery when switching Subdoctrines. This aims to reduce the rigidity of the new doctrine system.
Combat & Unit Rebalancing
Significant adjustments have been made to land unit experience, reducing the combat bonuses across all tiers. Self-Propelled Artillery (SPA) and Tank Destroyers (TD) have seen substantial nerfs to their soft attack, piercing, and technology progression to bring them in line with other units. Conversely, Armored Cars have received a production cost reduction to improve their viability.
Naval & AI Updates
Naval doctrines have been rebalanced, specifically targeting Anti-Air and Torpedo effectiveness. The AI has also been tuned to be more conservative with fleet operations, now seeking repairs at a 75% strength ratio instead of 65%.