This BattleTech RPG bundle by Catalyst Game Labs is $18 for:

MechWarrior: Destiny (2020) - RPG based on Cue System, a narrative RPG system
A Time of War: The BattleTech RPG (Revised) (2022) - RPG with 2d6 roll mechanics

CAT-35252 Field Manual: 3145 (2013) - source book
CAT-35701 BattleTech: Legends (2021) - 52 MechWarriors and their Mechs
CAT-35900 Shattered Fortress (2022) - source book set in 3146 Republic of the Sphere
CAT-35901 BattleTech: ilClan (2021) - source book
CAT-35902 Tamar Rising (2022) - source book set in Clan Jade Falcon Occupation Zone in 3151

CAT-35SN501 House Arano: The Aurigan Coalition (2019) - source book based on PC BattleTech game

CAT-35001 Total Warfare (2006) - Classic BattleTech board game complete rules
Force Manual: Davion (2024) - source book for BattleTech board game
Force Manual: Kurita (2024)- source book for BattleTech board game

CAT-35680 Alpha Strike: Commander's Edition (2019) - board game rules for fast-play version of BattleTech

BattleTech Universe
Battlemech Manual
BattleTech: Recognition Guide, Vol 1: Classics
BattleTech: Recognition Guide, Vol 2: ilClan
BattleTech: Hot Spots: Hinterlands
BattleTech: Era Report: 3145
BattleTech: Empire Alone
BattleTech: Dominions Divided

I did not finish organizing this list because I realized this is such a hodgepodge of material. Why include the two board game rules plus supplementary material? At least most or all the material is Dark Ages or post Dark Ages. Still, BattleTech is such a massive universe of published products we'll just get overlapping bundles so I'd like something that I'm more confident will not be in other bundles.

I will skip.