Call of Duty: Modern Warfare 4 — October 29 Update: Possession Mode, XP Boosts and Every DMZ Change Explained
Call of Duty: Modern Warfare 4's October 29 update adds the new Possession Halloween party mode, boosts multiplayer XP earn rates, fixes issues on Lithium, Silkworm, Mumbai and Shipment, and increases DMZ cash rewards while patching Hajin terrain bugs. Here's everything confirmed, plus the weapon, movement and DMZ changes from earlier in the week.
Call of Duty: Modern Warfare 4 shipped on October 23, 2026, and Infinity Ward has been pushing changes almost every day since. The October 29 update is the biggest one yet: it adds a brand-new Halloween party mode called Possession, raises XP earn rates across several multiplayer playlists, fixes a handful of map bugs, and increases cash rewards in DMZ while patching a nasty Hajin terrain issue.
This guide breaks down everything confirmed in Infinity Ward's own patch notes for the October 29 update, plus the weapon tuning, movement fix and DMZ changes that landed earlier in the week so you have the full picture of where Modern Warfare 4 stands heading into its first week.
1. What's New in the October 29 Update
Infinity Ward's October 29 patch notes cover three areas: multiplayer, DMZ and a note on upcoming content. The headline additions are:
- Possession added as a new Halloween Party Mode in multiplayer.
- XP earn rates increased across several multiplayer modes.
- Map fixes for Lithium, Silkworm, Mumbai and Shipment, plus a Domination scoreboard bug fix.
- Increased cash rewards in DMZ for Dynamic Ops, Side Ops and Story Mission replays.
- A fix for Hajin terrain issues and a crashing Exfil helicopter in DMZ.
It follows a steady cadence of post-launch patches: a DMZ early-access patch on October 20, the October 23 launch patch, fixes on October 24 and 25, a weapon tuning and Possum equipment update on October 28, and now the October 29 patch covering Possession and the XP changes above.
2. Possession: Modern Warfare 4's New Halloween Party Mode
Possession is the mode Infinity Ward teased back on October 14, when the studio posted its official post-launch roadmap on X. That roadmap dated three content drops in sequence: Shipment returning on October 27, Possession arriving on October 29, and Infected following on October 30 — all leading into Season 1 on November 6.
Possession went live with the October 29 patch as scheduled, listed under Party Modes with a pumpkin icon signaling Halloween theming. Infinity Ward's patch notes confirm the mode's name and launch date but don't yet spell out a full ruleset beyond calling it a new Halloween Party Mode, so treat specifics about how scoring or objectives work as unconfirmed until Infinity Ward publishes a dedicated breakdown. Infected, the next mode on the roadmap, wasn't mentioned in the October 29 notes, so it's worth checking back before assuming it's live on schedule.
If you're trying to decide what to play first this week, the Kill Block multiplayer mode is also still in rotation alongside the new Halloween additions.
3. Multiplayer Changes: XP, Maps and New Playlists
Outside of Possession, the biggest multiplayer change in the October 29 patch is the across-the-board XP increase, which should speed up weapon and Battle Pass progression in the affected modes. Infinity Ward also quietly fixed map issues on Lithium, Silkworm, Mumbai and Shipment, and corrected a bug that was causing the Domination scoreboard to display incorrectly.
This builds on changes from earlier in the week:
- October 27: Shipment 24/7, Kill Block 6v6 Gunfight and Gun Game were added as new playlists. Free-For-All's score limit was set to 30.
- October 28: The Quick Fix perk no longer regenerates health while you're actively taking damage, closing a tanking exploit.
- October 25: Kill XP in Search & Destroy and Collateral was raised from 100 to 300, and a fix for the "bomb stretching" exploit was rolled back after it caused other issues. Infinity Ward says it will address bomb stretching again once it has a stable fix.
- October 24: Hijack spawn and respawn points were improved alongside several other map and mode fixes.
For the full list of confirmed maps and modes at launch, see our Modern Warfare 4 multiplayer maps and modes breakdown.
4. Weapon Balance and Movement Tuning
October 28 brought the game's first proper weapon tuning pass since launch. Infinity Ward normalized hit-location damage to produce a more consistent time-to-kill, with the bulk of the changes targeting upper-limb damage multipliers on SMGs. This follows the baseline tuning already in place at launch, where SMGs were made more efficient in close-to-mid-range fights and one-hit-kill weapons had their flinch and damage values tempered.
Alongside the balance pass, several bugs were fixed:
- A visual issue with the Mosin-Nagant's firing pin.
- An incorrect time-to-kill display on the Rezi 12.
- A bug affecting the M4's muzzle attachment.
- The Patriot XMR, Oden and Cronen Squall were misclassified as Battle Rifles and have been corrected.
On movement, Infinity Ward reduced dive velocity by 23% to curb a sprint-jump dive speed exploit that let players cover ground unrealistically fast. The studio has said a long-term fix is still planned, so expect further movement tuning. Full details on the launch weapon and movement changes are in our Modern Warfare 4 launch patch notes guide.
5. DMZ: Cash Boosts, Hajin Fixes and a Known Vest Issue
DMZ got its own round of changes on October 29. Cash rewards were increased for completing Dynamic Ops, Side Ops and Story Mission replays, making extraction runs more worthwhile. Infinity Ward also fixed terrain issues around Hajin, the DMZ exclusion zone built around the Forward Operating Base, and patched a bug that was causing the Exfil helicopter to crash. One known issue remains: the 3-Plate Armor Vest reward tied to reaching Level 37 only applies correctly to players who hadn't already hit that level before the fix went in.
Earlier DMZ changes this week included:
- October 28: The Possum equipment was tuned so it can't be activated while the team that killed you is nearby, and now has a roughly four-minute cooldown before it can be used again; both the range and duration remain adjustable going forward.
- October 25: Drill Charge damage against the Colossus enemy type was decreased.
- October 23 (launch): Gas Mask and Parachute usage counts were corrected, and Disposable Parachutes now have three uses instead of the launch default.
For everything confirmed about the DMZ map itself, read our Hajin and Forward Operating Base guide.
6. What's Still to Come
A few items are flagged for later but don't have firm dates yet:
- Infected mode is slated for October 30 on Infinity Ward's October 14 roadmap, completing the Shipment-Possession-Infected sequence, though it wasn't mentioned in the October 29 notes.
- A future backend update will restore Final Killcam in Free-For-All.
- Season 1 arrives November 6 for both Modern Warfare 4 and Warzone. Weekly Challenges won't be part of it at launch, but events will recur.
- Apex Attachments are confirmed to be returning "soon," with no date given yet.
- Further weapon tuning was teased for "next week" as of the October 23 notes, on top of the October 28 pass.
- A proper fix for the bomb-stretching exploit is planned once Infinity Ward has one that doesn't cause side effects.
Quick recap: the October 29 update's biggest additions are the Possession Halloween mode, multiplayer XP increases, map fixes on Lithium, Silkworm, Mumbai and Shipment, and bigger DMZ cash payouts with a Hajin terrain fix. Weapon and movement tuning from October 28 is still settling in, and Infected mode and Season 1 are the next things to watch for. Browse our full Call of Duty guide archive for more on Modern Warfare 4.