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Halo Campaign Evolved CU3: every tag the July 29 update changed

MJOLNIR Coregame-updatecu3tag-data

Halo Campaign Evolved shipped its first Steam patch, CU3 (2026.07.25.1112544.4-Rel-i343-Meteorite-2607-CU3), on July 29 — six days after Early Access began. We snapshotted the launch build and CU3 and ran every one of the game's 12,291 Blam tags through a field-level diff. The verdict: 1 tag added, 0 removed, 375 changed, 11,913 byte-identical.

There is no CU1

The build Steam launched with is stamped 2026.06.26.1097863.1-Rel-i343-Meteorite-2606-CU2 — "CU2", on day one. The content-update numbering predates the Steam release, so the oldest build Steam ever shipped is CU2: it went out as the Early Access preload on July 23, the July 28 wide release served the same depot manifest, and the depot's manifest history contains nothing older. If you are looking for a "CU1" or a 1.0 before it, it does not exist on Steam — the CU2-stamped build is the original PC release, and it is archived in our snapshot store. Every diff in this series is anchored to it.

B40 got the biggest encounter rework of any update so far

Assault on the Control Room's scenario carries over 1,300 substantive field changes and a new script (664 → 665). The flavor of it: one squad's spawn point went from no activity to patrol, its patrol mode flipped from ping-pong to loop, and it was handed a patrol point set it previously didn't have; other squads were reassigned to different point sets; spawn positions were nudged. Somebody spent real time in B40's encounters for CU3.

The rest of the campaign got surgical edits

  • A30 (Halo) — an AI objective task gained a second area, flagged as a goal: an encounter was literally given a new place to push toward.
  • A50 — one spawn point delayed by 4 seconds and lowered ~2 units.
  • B30 — two spawn points moved about two units and given real facing angles.
  • C20 — one squad's character type swapped (#6 → #0).
  • C45 — one squad's template swapped.
  • E20 — squad templates renumbered across ~30 squads and scripted unit seats rebound.
  • e30 — AI pathfinding hint data adjusted in eight places.
  • Both campaign variants in game_engine_settings got new encounter remix initial random seed values, so remixed encounter layouts roll differently than at launch.

The one new tag: an animation graph for a c40 Banshee door (objects/Levels/halo1/solo/c40/banshee_door/banshee_door1_c40).

The remaining ~330 changed tags are cooker noise, not design: 175 animation graphs whose bytes moved with no visible field change, level-geometry BSPs full of runtime pointer churn, lighting checksums, seam renumbering.

Two launch-build curiosities, for the record

Diffing against launch also settles what was already there. The oddly named Cinematics/020la_sword/.../jorge_turret animation graph — a Reach character's cinematic rig under a naming scheme matching no shipped mission — is present in the launch build. It is launch-era content, purpose unknown; when it changes, we'll know the same day. And two level-geometry chunks defeat our built-in Oodle decoder on both builds — a gap in our tooling that has been there since launch, not something a patch did. (Update, August 19: the decoder is fixed — both chunks now decode on every build.)

How this post was made

Steam patches in place, but its CDN still serves older depot manifests, and a recovered build is not an approximation: our recovered CU3 hashes bit-for-bit identical to the live install, on all 252 shipped files. Both builds live in a content-addressed snapshot store, and mjolnir tagdiff compared every tag and decoded every changed one, field by field.