What Infinity Ward actually changed
Modern Warfare 4 Beta Patch Notes
The August 2026 beta was not a frozen build. Infinity Ward patched almost every day of Weekend One, shipped a systems rewrite for Open Beta on August 28, and kept tuning through September 1. This page is the public record so a loadout video filmed on August 21 is not treated as gospel on October 23. Parent access questions stay on beta codes. What to play sits on how to play the beta.
Sources: official Call of Duty patch blogs as reported by PCGamesN, Eurogamer, Dexerto, and MW4.GG. We do not invent numbers. Headshot multipliers below are from those notes.
August 22 — Cachette, Inflation, footsteps
Day-two patch. New 6v6 map Cachette (French rail terminal, wine warehouse and mechanic’s garage) so map voting could turn on — IW said they needed four maps. New mode Inflation. Frangible rounds: slow duration −26.8%, magnitude −21.4%. ISO Nightshade and Oris 8.6 were cut. Enemy footstep and gear audio: shorter range, lower volume. Transit 213 lighting was brightened.
Bug fixes included Mobility Course start/complete failures, wet-surface footstep audio, Gunsmith errors, and opaque magnified optics while ADS. This is the patch that made Ninja less of a tax.
August 23–24 — Lotus, Gunfight, TTK
August 23: Lotus entered 6v6 rotation, 3v3 Gunfight on Kill Block, Transit 24/7 playlist later that day. Attack Helicopter health −45%. Headshot multipliers cut on M4 (1.5 → 1.2), Patriot XMR, Kastov 762, ISO, PPSh-41, X-58 Nyx, FiNN, Type 73. Firing Range lighting adjusted. Xbox missing-pack install improved.
August 24: further TTK surgery on M4, HAN 86, Axion, MAR-9. 10v10 Gunfight on Kill Block removed until Weekend Two; 3v3 stayed. Cachette out-of-bounds exploit fixed. Lobby music leaking into matches fixed.
August 28 — Open Beta rewrite
Weekend Two was billed as a gameplay rewrite, not a content drop: TTK, spawns, movement, killstreaks, aim assist. New 6v6: Lithium. New mode: Hijack. Zodiac Resurgence Quads live. Combat Outpost (Imjin Farmland, Wolves Stadium) Saturday. Level cap 30. 10v10 Gunfight returned. Hardpoint on Rooftops was disabled as a known issue. Hijack’s Data Spike could become unrecoverable.
Eurogamer’s Steam chart note: Weekend Two numbers barely moved even with Warzone attached. That is population data, not a map review. For the guns after these cuts, tier list. For Zodiac, Warzone.
August 31 – September 1 — last days and wrap
August 31 was the last full Open Beta day. Double XP and Double Weapon XP stayed on; Transit 213 24/7 and 6v6 Gunfight on Kill Block remained in the playlist. Level 30 unlocked the Beta Forged Blueprint. Weapon pass: ISO Nightshade max 20 → 21 and head 1.25 → 1.3; PPSh range out a metre; FiNN max 33 → 30; Type 73 max 28 → 22; Oris 8.6 max range 20.8 m → 19 m; Han 86 max 22 → 23; M4 Hurricane Apex max 30 → 27 and head 1.3 → 1.25; Rezi 12 long barrels lost range bonus. Zodiac got visibility, armor-plate hold time, and infil-pistol retunes.
September 1 close-out: Infinity Ward thanked millions of players, then listed launch homework in public — TTK still not where they want it, perk tiers that actually mean something, more aim-assist work, spawn fixes on specific map/mode pairs, Switch 2 performance. Warzone homework: HUD readability, footsteps, grounded movement, Zodiac pacing. The beta ended 10pm PT. The next public notes are launch-week, not a third weekend.
Related intel
Section hub
Field questions
Frequently asked questions
Did they nerf the M4 in the MW4 beta?+
Yes. Headshot multiplier 1.5 to 1.2 on August 23, with more range and TTK cuts on August 24. The Hurricane Apex lost more damage on August 31.
When did Cachette and Inflation ship?+
August 22, 2026, the first content patch of Weekend One.
What did Open Beta add?+
Lithium, Hijack, Zodiac Resurgence, Combat Outpost, level cap 30, Tac Sprint on Blood Rush, and a systems pass on TTK, spawns, movement, streaks, and aim assist. It closed September 1 at 10pm PT.