Howdy ‘mechwarriors and welcome to… not a ‘mech review! No, today we’ve got something very different and very rare: Core Rules Changes.
That’s right, Catalyst is playtesting new core rules for the game and you, yes you, can help play test them! They’re going to be rolling them out in waves starting with survivability rules. Now, there are only two changes here but they are incredibly important changes so we’re going to go over them.
Catalyst’s page with the playtest updates can be found here.
Note that this is just a new core rule book and as such is not a new edition or a cutdown or any of that. This is an update to the core rules of a game that has been fundamentally unchanging and unyielding in its path since the year of our lord 1990, fun fact reader that is older than either myself or Peri. By several years.
Feel old about it.
We feel old about it because we’ve played a lot of BattleTech against a lot of people who were younger than Total Warfare. This whole ‘time’ thing sucks.
So, speaking of time, what’s this roll out look like? Well, according to Catalyst’s official page on the matter, this:
Package 1: Survivability Rules, this one, is going to run from now until October 13th.
Package 2: Mobility Rules, will go from September 29th to November 10th.
Package 3: Gear from October 27th to December 8th.
Package 4: Missions runs from November 24th to January 5th.
Package 5: rules for BSPs which currently has no start date but has a projected end alongside Package 4.
Package 4 is an interesting thing on the face and I’m excited to see what’s in it as a standardized format, or at least mission set for BattleTech is something we see people asking for a lot and it’d be great to get something in that matter!

Table of Contents
The Announcement
Liberty: Catalyst has announced that they are working on these new core rules and I’m… excited? I’ve only been playing BT for around 2 years now and have fallen into quite the groove with it so far and am having a blast with this game.
That said Total Warfare, and much of the BT system in general, can be rather clunky for those who aren’t as… ingrained into it as I have made myself to be and as such some changes are likely in order. There’s more than a handful of odd bits floating around in BT’s guts that could certainly use some attention so I’m hoping that what they do in these playtest packages addresses the rough spots!
I also hope that the changes that are coming aren’t too… much. The document indicates that they’re aiming to keep BT as it is and that attitude is exactly what I’m hoping for. BT is a great game and, flaws or not, is one of the few wargames that really grabbed my attention. I adore this game and I’ve got hopes, and reservations, for what’s coming in the rest of the playtest roll outs, so let’s see what we’ve got in this one.
Peri: This is more or less what I was expecting to happen at some point in the next couple of years, though I was expecting them to announce it specifically for the 20th anniversary of Total Warfare. Total Warfare is, to be blunt, a bit of a terrible rulebook, extremely unfriendly to read and, layout wise, a total mess. With the game getting more and more popular, issuing a new Core book somewhat like the BMM makes a lot of sense.
In terms of scope, if you are more on the 40K end of things, this is likely to be more like that game’s mid edition updates in terms of scope. Not a revamp or overhaul, just an adjustment to a number of elements of the game to smooth things over a bit.
I am personally massively excited about this. I like the philosophy they state in the document towards the game: That a radical change isn’t needed or wanted, but some clarifications and sanding down some rough edges would be nice.
If anything, the thing that excites me the most has nothing to do with rules changes; it’s entirely just Total Warfare getting re-written. I have been playing BattleTech out of that stupid book for decades and I still miss things and play shit wrong because of how hard it is to find the information you are looking for. Battle Armor has been a significant source of arguments for me lately, so I am excited to see those rules in particular get a new layout and some usability passes.
One thing to note is that they have the list of playtests in this document, and #4 is “Missions.” If we are about to get a standardized Mission set for this game, I’ll cry. The game needs it like the desert needs the rain; getting a game started and together without any guidance on points levels or mission objectives is a total pain in the ass for new players.
Jack: Liberty and Peri have touched on most of my thoughts already, but my main one is that much like change for the sake of change isn’t necessarily good, neither is keeping rules static because you value their unchanging nature more than you do good play. I think everyone who plays BattleTech has found spots that are confusing, slow the game down, or otherwise don’t feel right, and I’m a fan of taking an opportunity to sand down some of those rough edges.
Proposal 1: Side Hit Location Changes
Peri: The gist of this section is that the side hit tables are going away, and instead when you hit someone in a side arc, you use the front hit table and treat any result on the opposite side as if it had hit the side you are in instead. So a right arc shot that reads left arm will just hit the right arm.
This has some implications for the math and positioning of the game; you will get hit in the center torso from the sides a bit more often, and it lets you really focus damage into specific parts of an enemy mech with good positioning. Interestingly, with core rules, this means that all TAC results will always hit the center torso, removing a major weakness of side torso ammo and making CT ammo far worse, even with the changes in proposal 2. This implies to me that some sort of TAC rework might be in one of the other documents, possibly Floating TAC being made core rules, but at current this is just an odd quirk of this change.
The purpose of this change in my eyes is pretty simple; it is just removing two charts that you would need to memorize, that being the side punch tables and the side hit tables. This will cut down on the load for new players who are learning the game, and it will in general make things a bit more consistent. Mostly a usability change, but it also adds more strategy to the movement component of the game; you can keep an open side torso away from the enemy, or position to pile damage into an enemy’s open side torso.
Overall, I think this is a positive change that isn’t going to shake the game to its core or anything. I do think that I will be trying to aggressively look for flanks now though, because focusing damage on a smaller number of hit locations is very, very strong in this game. Side arc shots already did that, but these changes will help you funnel damage even more with good positioning. I expect to see things like the Fire Falcon E and other high speed ATM machines to benefit the most from this, as it’ll let them focus their insane burst damage into a smaller number of hit locations.
Liberty: I’m, ever so slightly, annoyed by these specific changes. Not because I think they’re bad mind you, just because I finally memorized the current side charts so I could bully Peri about it and now feel like an idiot. This is bullshit.
That said, these changes are fine, I suppose? My only real problem being that I would personally like to keep the opposing limbs on the hit chart. Now, this is not because I think taking them fully out of the equation is wrong or makes side shots too punishing but because I figure, if placed at the 3 and 11 positions they’d be rare enough, only slightly less rare than a head hit or a TAC, as to not really matter but still do a good job of representing a shell catching a limb that’s hanging out on the edges of the ‘mech.
Not necessary, but fun for narrative. I think the rest of this is quite positive, actually! Making it a far more simplified chart will certainly make teaching new players easier and, for my beloved tournament scene, resolving hits from different arcs a fair bit faster! As well there’s a great result here of being able to fully dictate what side you want to try and chew off of your opponent which is a wonderful reward for having out maneuvered your opponent. The amount of times I’ve gotten around a target to bias shells into the more battered side of a ‘mech only for every shell to find the opposing results?
Maddening.
Jack: I lean towards positive sentiment towards this change, but I am a little concerned on the balance of it.
On the pro-change side, the side tables slow the game to a crawl. While most people I play with have at least a decent idea what the front table is like, there are very few people who have memorized the side tables. Every time someone gets hit in the side, especially if by an SRM, the game slows as they have to reference the table for each hit. It’s made doubly worse by people realizing after a couple hits that they were reading the left table instead of the right, or that they’d accidentally used the front table. This change would speed that way up and probably mostly get rid of the need to backtrack because you used the wrong table.
On the anti-change side, this allows fast mechs to concentrate damage extremely well to the point that I think I’d generally get side shots than rear shots. It’s a not insignificant change to hitting any given location – the chance to hit the side torso is 10/36 instead of 6/36, that side arm arm is 10/36 instead of 7/36, and that side leg actually drops to 8/36 instead of 9/36. Overall it’s a 75% chance to hit one of the side locations (the remainder being the CT or head), and previously it was a 61% chance (with part of the remainder being the opposite side as well as the CT and head. Being able to repeatedly get into a side arc is going to be a great way to ensure kills, especially on anything with an XL engine.
It makes positioning a lot more important, which is another aspect I’m a fan of – you can both use positioning to attack a specific side and try to defend a side in a way that you couldn’t do as reliably previously. It’s great for making high-skill play more meaningful, but I do end up concerned that the power is biased a little too far towards the attacker.

Proposal 2: Explosion Damage Cap
Peri: This is the big one, the important one, the massive, massive change. Ammo explosions are now capped at 20 damage when un-CASEd, 10 damage with CASE, and 1 damage with CASE II. In addition, if you survive an ammo explosion, you only lose your rear armor on the location that was carrying the ammo.
This means that an ammo-bin TAC is no longer the death of most mechs, with anything bigger than a light mech surviving a side torso ammo TAC, and a lot of assault mechs even surviving CT explosions with no CASE. With CASE things are hugely changed, with most mechs straight up being fine save for pilot hits after having a bin cook off. Standard Engine plus CASE assault mechs like the Hauptmann and Kingfisher are now immensely better, and they were already good.
The implications of this are frankly a bit earth-shaking when it comes to mech quality. A lot of Intro-tech shitmechs that are held back by ammo bombs and un-CASEd ammo in general improve massively. It can’t be overstated how much better something like a Highlander 733 is when it can’t randomly blow up at any moment and die instantly.
Another effect of this is that XL engines with CASE will actually do something now. On something like one of the advanced tech Marauders or Warhammers that mount XL engines, CASE, and random secondary weapon ammo, they will now survive an Ammo TAC and have plenty of fight left in them. Hell, they can probably survive an internal hit or two and an ammo crit without dying.
This will massively reduce the risk of mechs instantly super-dying by taking 300 points of damage out of nowhere from a TAC, and in general things will likely live a lot longer. Ammo is one of the main causes of Sudden Mech Death, and massively reducing the damage that you take from them is possibly the most significant core rules change the game has ever had.
Liberty: The ‘Make Marauders good and stuff’ change. This is a great change and will wildly help some of BattleTech’s more… flighty designs. Like the MAD-3R for example! Being able to survive a bin going off really ups the amount of heat some of those early intro-tech shit buckets can take. Anything that allows me to drag out more shit-bricks without worry of them dying the instant lego-man death I am here for.
The amount of Intro-tech heavies and assaults that this buffs from ‘eh’ to ‘usable shitbrick’ territories is breath-taking and I am here for it.
As well it means a CASEd out XL is not the death knell it once was, and now does something beyond the fluff of keeping your ‘mechwarrior, and their ‘mech, in better shape when the bins go off. The MAD-5T, and many other ‘mechs just like it, just got a good buff to their survivability, being able to not worry quite as much about the off switches they used to have.
This is also astounding for Succ’ Wars refits that bump padding in the same areas as the ammo like the MAD-3M, Victor VTR-9B, basic Orions, and the 3S Banshee spring to mind. This also buffs Heavy Gauss Rifles and HAGs as their previous MONDOMAN damage from explosions has been capped into the same range bands as the ammo explosions as they are components!
Now, it’s rather entertaining that this is a Damage CAP, meaning that if the bin that goes off has less than 10, or 20, damage in ammunition left in it you’ve still gotta figure out just how much is in there. I’ll run it out real quick for you so you don’t have to fiddle with it if you’re testing them out!
AC/2s: 4 Shells remaining for CASE, 9 for un-CASEd
AC/5s: 1 Shell remaining for CASE, 3 for un-CASEd
AC/10: can’t get below for CASE, 1 for un-CASEd
AC/20: LOL, LMAO even.
PAC-2: See AC/2.
PAC-4: 2 Shells remaining for CASE, 4 for un-CASEd.
PAC-8: 1 Shell remaining for CASE, 2 for un-CASEd.
SRM-2: 2 Salvos remaining for CASE, 4 for un-CASEd. Fun Fact, if you get an SRM-2 bin this low write into the site, I am in awe of you and wish to know your wonder. No the Drillson or whatever that are covered in SRM-2s don’t count, ya goobers.
SRM-4: 1 Salvo remaining for CASE, 2 for un-CASEd.
SRM-6: Can’t get below for CASE, 1 for un-CASEd.
LRM-5: See AC/5.
LRM-10: See AC/10.
LRM-15: Can’t get below for CASE, 1 for un-CASEd.
LRM-20: LOL, LMAO even.
ATM-3:
- HE: 1 Salvo remaining for CASE, 2 for un-CASEd.
- STD: 1 Salvo remaining for CASE, 3 for un-CASEd.
- EXTD: 3 Salvos remaining for CASE, 6 fur un-CASEd.
ATM-6:
- HE: Can’t get below for CASE, 1 for un-CASEd.
- STD: Can’t get below for CASE, 1 for un-CASEd.
- EXTD: 1 Salvo remaining for CASE, 3 for un-CASEd
ATM-9:
- HE: LOL, LMAO even.
- STD: Can’t get below for CASE, 1 for un-CASEd.
- EXTD: 1 Salvo remaining for CASE, 2 for un-CASEd.
ATM-12:
- HE: LOL, LMAO even.
- STD: LOL, LMAO even.
- EXTD: Can’t get below for CASE, 1 for un-CASEd.
Small Chem Lasers: 3 Shots remaining for CASE, 6 for un-CASEd.
Medium Chem Lasers: 1 Shots remaining for CASE, 3 for un-CASEd.
Large Chem Lasers: 1 Shot remaining for CASE, 2 for un-CASEd.
Machine Guns: Uh… look dude, I’m gonna level with you. If you get to a point that you need to know how many shots an LMG, MG, or HMG has before it hits the cap, 19, 9, 6 Un-CASEd, 9, 4, 3 for CASEd, you’re either doin’ weird shit or being rude to your opponents. Stop doing that.
Jack: I’m 100% on board with this change. As funny as big ammo explosions taking out an entire mech are, they aren’t hugely fun to be on either side of if you’re trying to play seriously as it’s such a huge swing. These damage caps are high enough that they’ll still be crippling to a ‘mech (remember, ammo explosions transfer inwards ignoring armor), but not so crippling that you can’t keep using the ‘mech at all, which ties back into the common gradual reduction of capabilities as you take damage that you get from the rest of the game.
Final Thoughts
This looks interesting, and perhaps even promising! Peri and I will actually be getting a game in explicitly to test these new rules out on Wednesday so look forward to some more firmed up opinions on them coming soon!
Until then! Fair weather, good seas and happy testing!
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