Still better than the Orion IIC.



The Orion has a long and storied history in canon; most notably as Kerensky’s mech of choice. And, as the first 75-tonner to be introduced to MWO, there was a lot of excitement around its release. But the mech almost universally disappointed with its shoddy hitboxes, super-spread hardpoints, and low weapon mounts. Since then, quirks have pushed it into the realm of the viable, but it’s still not a mech that gets picked a lot.

The best variant, by a fair margin, is the ON1-V. This is thanks in large part to its jam chance quirk, but it’s got a bunch more on top of that. The next most special variant is absolutely the ON1-VA, as it has 4 missile hardpoints and fantastic quirks for all of that, too. Next up is the Protector – it’s a hero mech and I don’t think it’s worth the MC, but it is a bit better than the other offerings. If you don’t want to go with that, I’d recommend the ON1-K, as it isn’t all that bad. Which kind of does mean that the ON1-M is…


Chassis-Wide Information


  • Some of the best quirks in the game – 50% extra structure, solid agility for all, and some really amazing weapon bonuses to boot.
  • 75 tons gives you as much room to work with as is possible on an IS heavy mech.
  • Lots of build options. This is partially due to how very few builds are good enough to be a big deal, so the rest are pretty much on par…but I suppose build diversity is always a good thing.



  • Atrocious hitboxes – even after all of this time, they’re near the bottom of the barrel. The only mechs with clearly worse hitboxes are its heavy and assault IIC cousins.
  • Low mounts mean lots of shots get blocked by terrain on many maps. They’re not quite the lowest of any mech, but they’re pretty close.
  • The hardpoints are generally spread all over without much of a concentration on any one type, making it hard to effectively boat. Not quite as big a deal, but hurts quality of life.


Generic Tips

  • Since the mounts are so low, ranged styles are pretty much exclusively going to be either corner-peeking or suppression styles. As long as you’ve got a one-on-one engagement, you can win most trades just thanks to your crazy quirks, but use your own judgment in such situations.



If you’re not familiar with my Inner Sphere Master Guides, each pretty much follows the same formula. Each variant gets its own section; within that section I try to include at least two main builds, each with a few variations on the core principle (if applicable).

Each build has one paragraph about the build itself – going over anything I feel is relevant to understanding it such as quirks, tonnage issues, how it fits the meta, my general feeling about it…just whatever. And then there’s a paragraph about using the build, going over tactics, tips, and whatever I feel is relevant to that, including links to L2P guides, on occasion.

I may miss a build that you like, or my builds may differ slightly from what you find works best for you because our philosophies may differ – I strongly encourage that you experiment for yourself to see what works best for you.

The modules are listed in order of which one is most important and the consumables I’ve listed are the ones that are generally the best, but while leveling the mech you may want to swap the less important consumable out for a UAV. That is, if you can afford to use consumables at all (they aren’t necessary, just nice, and if you’re low on C-Bills they’re not necessarily worth it).

On with it!



This variant gets a spectacular 20% ballistic cooldown quirk to go with a 30% UAC jam chance quirk, making it the heaviest mech that can run 2 UAC/5s with a 30% reduced jam chance. It also gets 20% energy cooldown and 15% missile cooldown. After that, it’s got 50% extra structure across the board, 25% turn rate, and 35% for accel/decel and torso twist speed.

Build 1:

The weapon loadout isn’t terribly imposing at first glance, but when the quirks come into play it’s absolutely brutal – the UAC/5s have a 1 second cooldown, so without jamming you’ll be at 20 DPS, on top of the large laser damage. It’s not on quite the same level as a Mauler or Dire Wolf, but it is awfully close.

You don’t want to waste time with poking or hill-humping in this mech, but you can’t quite hold up in a brawl either. So when defending, you’ll want to settle on an overlook-style position, where you can get a good burst off on anyone that tries to poke. But if you’re more aggressive (which you always should be), try to play around to get odd angles on the enemy’s wings – there are very few mechs that can hold up against this thing without support. A lot of times, this ends up being something like a slow rotation, but play it by ear.

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: UAC/5 Cooldown, Large Laser Range

Consumables: Cool Shot, Air Strike

Oof, it’s hotter and slower and has less ammo, but it’s even more brutal. I don’t think it’s worth it, since the lasers really aren’t the focus of the build and the speed is important, but it’s not bad at all.

Weapon Modules: UAC/5 Cooldown, LPL Range

It’s sub-optimal in a few ways, but the brawling damage is absolutely brutal.

Weapon Modules: UAC/5 Cooldown, SRM6 Cooldown

Not enough ammo, speed, convergence, PPC velocity quirks, or heatsinks…but you can do it, I guess. Dunno why you would.

Weapon Modules: UAC/5 Cooldown, PPC Cooldown



Honorable Mentions:

The dakka build really is the entire point of the ON1-V, but if you get bored there’s other options.

Soooo bad. I mean, goddamn that’s horrid. But still, it’s funny.

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: SRM4 Cooldown, LBX10 Cooldown

Consumables: Cool Shot, Artillery Strike

I’m not sure if it’s any better…it’s got more speed, but worse spread and less ammo. But at least you don’t have to take ferro off, coming from the UACs.



With 4 missile hardpoints, 25% to missile cooldown, 15% to missile heat gen, and 10% to missile velocity, this is the obvious brawler. On top of that, it’s also got 15% to ballistic cooldown and velocity. And then, of course, 50% extra structure, 15% turn rate, and 35% accel/decel and torso twist speed.

Build 1:

It’s the perfect hybrid between devastating firepower and mediocre speed. Seriously though, I love this build just because of how perfectly it fits, and it ends up working out pretty well when you play it too. In Smurfy it looks pretty good, but when you factor in it having better missiles than an Oxide and a pretty powerful AC/20…it paints a very pretty picture. It doesn’t always hold up in game, but that’s just life isn’t it.

This mech is as brawly as it gets, just a shade less powerful than the AS7-S. But playing this mech is even less forgiving, and you really do have to avoid enemy fire until you can actually engage. Once that happens, it plays like any other brawler, but the incredibly un-sync’d nature of the weapons makes shielding a chore. Try to roll as much damage as possible, but…also try to deal as much damage as possible. If you can manage to lose your LT before your RT, fantastic, but you know what they say: the best defense is a good blowing-the-bad-guy-up-fast.

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: AC/20 Cooldown, SRM4 Cooldown

Consumables: Cool Shot, Artillery Strike

I mean…it’s slower than a snail. But it does a lot of damage – more than an Atlas, actually, thanks to its quirks. But the weaknesses are just a bit too much for my taste.

Weapon Modules: AC/20 Cooldown, SRM6 Cooldown

Much less upfront firepower to be sure, and a whole lot less survivability (you do usually lose a side torso first), but that speed is fantastic. And on this build (with the right modules) your missiles and cannon have a much closer sync-up.

Weapon Modules: SRM4 Cooldown, AC/10 Cooldown

This throws the ballistic out altogether, opting instead for something which resembles a jumbo Griffin, with the heatsinks and ammo to drive your firepower for a long time.

Weapon Modules: SRM6 Cooldown, MPL Range


Build 2:

Hey, at least it has one useful weapon on it, right! Right, guys? Guys?

But yeah, it’s a LRM boat. This build is focused on keeping your LRMs focused and high-DPS, and it has a Large Laser for if you get bored and want to contribute to the fight. You should be fast enough to reposition as necessary, and your 25% cooldown quirk means you can fire 2 LRM10s every 1.2 seconds, which is a pretty good DPS if you manage to get a quarter of your missiles to hit CT.

Mech Modules: Target Decay, Seismic Sensor

Weapon Modules: LRM10 Cooldown, Large Laser Cooldown

Consumables: Cool Shot, UAV

lol its dum

Weapon Modules: LRM15 Cooldown, LRM15 Range



This variant gets 10% to ballistic and energy cooldown, laser duration, and missile velocity, plus 15% to just Gauss Rifle cooldown and 5% to missile cooldown. It has the same 50% bonus structure as the others, and 45% to accel/decel, 15% to turn rate, and 35% to torso twist speed.

Build 1:

It’s a bit toasty and it’s not exactly fast, but it’s a pretty sweet fit for both the meta and the quirks. You’re pretty solidly set at the mid-long range, and this is the second best option that the chassis gets at that range in general.

You’ll want to stick with your team most of the game, and try really hard to not get rotated on. Since you’re only going 66 KPH, that’s a tall order, but you should be fine as long as your team doesn’t go full NASCAR. Trading may be an issue due to your low hardpoints, but your cooldowns are low enough that you can keep making them if need be. In a lot of ways, this variant plays like the ON1-V, and for more about the Gauss Vomit playstyle you can check out the L2P guide.

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: Large Laser Range, Gauss Cooldown

Consumables: Cool Shot, Air Strike

I’m really not a fan of using an XL engine with a Gauss Rifle, but…maybe the speed and heatsinks are worth it for you.

In for a penny and all that. Lots and lots of damage, but very little survivability.

Weapon Modules: Gauss Cooldown, LPL Range

This gets to use an XL without risking the Gauss explosion, and has quite a bit of extra DPS. Unfortunately, while it is safer than an XL Gauss build, it’s not quite safe.

Weapon Modules: AC/5 Cooldown, Large Laser Range

This one’s a bit different, with a shorter-range focus, but manages to fit the meta very well still. Thing is, it’s done better on the ON1-V.

Weapon Modules: UAC/5 Cooldown, LPL Range

I like how it’s the same alpha strike as the first build, but at a much lower range. Fortunately, it makes up for the range with great DPS and high precision, not to mention its extra speed.

Weapon Modules: AC/20 Cooldown, LPL Range


Build 2:

These builds are pretty similar to the last one I talked about, but they play differently enough that I can’t consider them to just be variations on the same theme. This one is pretty old-school, using Gauss and Peeps to nail down 35 damage. Unfortunately, the lack of a velocity quirk holds it back pretty hard.

You want to be working on getting good angles to make this work, and you don’t have much range to do it with. The Gauss Rifle is great for distance, but without quirks, the PPCs will be unreliable past the mid-long range area. Get shots off whenever you can, but remember to shield with your left side if you think you’re going to take a hammerin’. For more on this style of build, check out the L2P Guide.

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: Gauss Cooldown, PPC Cooldown

Consumables: Cool Shot, Air Strike

Still very old-school, this gets you a fair bit of extra DPS out of the deal at the cost of some range and precision. It will also run hotter and slower, but still ends up coming out ahead in many situations.

Weapon Modules: UAC/5 Cooldown, PPC Cooldown



If you’re not looking to drop the big bucks on a Protector (which is probably a good idea), this is your best bet for a third variant. It has the most energy hardpoints, and gets a 15% to energy heat gen and 10% for cooldown, to go along with 15% ballistic cooldown and 10% ballistic and missile velocities. And then, of course, there’s the 50% bonus structure, 35% accel/decel and torso twist speed, and 15% turn rate.

Build 1:

It’s not the most Orion build out there, but it’s your best bet for this variant. The low mounts really hamper your ability to trade a lot of the time, but you can still corner-peek like a monster, and no mech in the game can just shrug off a 40-point blast. The lack of significant velocity quirks on these slow-moving weapons is a bit of a concern, but at the end of the day it’s not too bad.

When playing this, you kinda just wanna keep moving and hitting the bad guys until you find a nice spot to corner-peek from that will keep you in range. Then, just keep poking on them until you have to move for whatever reason (team rotating, enemies closing, etc.) Play it by ear and just always be looking for shots. For more on this style, check out the PPFLD L2P Guide.

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: AC/20 Cooldown, PPC Cooldown

Consumables: Cool Shot, Air Strike

Pretty decent brawler with some mid range potential, but it’s nothing particularly special in my experience.

Weapon Modules: AC/20 Cooldown, Large Pulse Range

Doesn’t quite fit with the other builds, but it’s close enough right…

Weapon Modules: Large Pulse Range, Large Pulse Cooldown

I don’t think the comparison is a favorable one for this build, but you do get a lot more range and somewhat faster projectiles out of the swap.

Weapon Modules: Gauss Cooldown, ERPPC Cooldown


Build 2:

It’s kind of lame as far as firepower goes, but it’s fast and it’s tough and it can put out a lot of damage if not focused down. Plus, it’s very concentrated damage, what with the pulse lasers and AC/20. It does get a bit hot, but the 15% energy heat gen quirk helps with that, too.

For the most part, this plays like any other brawler. Focus on getting into range without getting shot in whatever way you can, and strike at an opportune moment.

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: AC/20 Cooldown, MPL Range

Consumables: Cool Shot, Artillery Strike



There’s really no reason to get this variant over any of the others, but I might as well cover it a bit. It has 10% to ballistic cooldown and missile velocity, 20% to laser duration and bonus LBX cooldown, 5% to energy heat gen, and 15% to missile cooldown. On top of that, you get the 50% boosted structure and the 35% to accel/decel and torso twist speed, and finally, the 25% turn rate.

This build isn’t exactly brilliant, but it kind of is the most interesting/unique thing the variant can do. Really, I recommend you build out something that simulates the PPFLD ON1-K, or Gauss Vomit Protector if you bought this variant and plan on leveling it. But this is about as special as this one gets. I’d really love to make use of the LBX quirks, but just one hardpoint isn’t enough for that particular weapon system. I wish that the ballistic cooldown quirks had actually been switched between the ON1-M and Protector, so that this would end up with the Gauss specialty.

But I digress. Playing this will be just like any other brawler. It’ll be a lot like the other Orion brawlers, in particular, with just a couple unique things worth noting. Mainly, that’s around how its weapon systems actually sync up on cooldowns almost perfectly, so you should be firing-twisting-firing-etc. This also means you can spread damage better than on the other variants, so you might actually be able to get down to just your CT missile launcher. Good luck!

Mech Modules: Radar Deprivation, Seismic Sensor

Weapon Modules: AC/20 Cooldown, SRM6 Cooldown

Consumables: Cool Shot, Artillery Strike


Pilot Skills

I’ve figured that this is the best skill order for pretty much any mech, and so I’m just going to customize it for mechs that have to emphasize unusual pilot skills.

Basics: Cool Run – Heat Containment – Hard Brake – Kinetic Burst – Twist Speed – Twist X – Anchor Turn – Arm Reflex

Elites: Speed Tweak – Fast Fire – Quick Ignition – Pinpoint

Then just master it. I’d only bother with going all the way on the ON1-V for most purposes, but if you enjoy one of the other variants, go for it!


And that’s that. I hope you enjoy your mech, let me know if you have any questions, and as always glhf

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