Mistakes happen, and sometimes players come up with situations the BattleTech designers, writers and testers never imagined. If you believe you’ve found a problem, report it in the appropriate thread on our forum.  Catalyst rolls in all approved errata every time a product is reprinted.

Below is all official errata issued for our products. For books with multiple printings, check the last page of the credits section to determine what printing you have. If it’s any printing past the first, this will be noted on that page (e.g. “Corrected Fifth Printing”).

Errata last updated 14 October 2021.


A Game of Armored Combat Errata version 6.02

This PDF is 249KB.






BattleMech Manual Errata version 5.0





This PDF is 363KB.

In addition, there is one other download for the 1st printing of the BattleMech Manual. This corrects the 1st printing’s flawed flowchart on page 42:

BattleMech Manual Corrected Damage Flowchart p. 42


Total Warfare Errata version 9.0





This PDF is 622KB.


TechManual Errata version 5.0 – General Changes





This PDF is 759KB.

In addition, there are two other downloads for TechManual. The first replaces pages 302-314 as well as page 319, the second replaces pages 349-352. Both are featured in the third printing and up, but are released here separately for your convenience.

TechManual Errata version 4.1 – Battle Value (June 2021)
TechManual Errata version 4.1 – Infantry Weapon Tables (June 2021)


Tactical Operations Errata version 3.03

This PDF is 1,046KB.

This errata is for the single-volume version only.
In addition, there is one other download for Tactical Operations, for both printings, which adds landing modifiers for the various types of special terrain found in that book:

Tactical Operations Landing Modifiers


Strategic Operations Errata version 3.02

This PDF is 476KB.

Note that this is the original 448-page version of Strategic Operations, not the current version (subtitled “Advanced Aerospace Rules”, 184 pages).


In addition, there are two other downloads for Strategic Operations. The first replaces the Customization rules found on pp. 188-189, while the second updates the BattleForce rules to take advantage of some of the rule changes brought about in Alpha Strike.

Strategic Operations Revised Refitting v3
Strategic Operations BattleForce Update v1.3


Interstellar Operations Errata version 1.21

This PDF is 253KB.




Campaign Operations Errata version 3.0

Note that this errata is for the revised 256-page version of Campaign Operations, not the original 192-page version.

This PDF is 251KB.



A Time of War Errata version 2.02

This PDF is 158KB.




A Time of War Companion Errata version 1.1

This PDF is 229KB.




MechWarrior: Destiny Errata version 2.0

This PDF is 180KB.




Alpha Strike Commander’s Edition Errata version 4.1

This PDF is 357KB.





Alpha Strike Errata version 2.5

This PDF is 625KB.




Alpha Strike Companion Errata version 1.4

This PDF is 525KB.

In addition, there is one other download for the Companion, which clarifies the heat conversion process:

Alpha Strike Companion Converting Heat Errata version 1.2


TRO Clan Invasion Errata version 3.0

This PDF is 281KB.



Battle of Tukayyid Errata version 2.0

This PDF is 275KB.