Junk SPARK: This is the Derelict Spark from the Lost Towers mission. The cheapest and fastest unit to build. Their stats are unimpressive (besides their Armor) as a result of the low quality parts, but they can still provide support with Suppression, and have the ability to self-destruct if you really need some armor shredded or a wall destroyed. By default, a Junk SPARK takes 3 days to build in an unmanned Proving Grounds for just 10 supplies. They are unlocked with Hybrid Materials research.

Resistance MEC: The Resistance MECs encountered in LW2 and LWOTC, that would be sent to defend havens. The ones in this mod, though, can be used just like a regular soldier. They're a little stronger than an Advent MEC, around the same power as a vanilla SPARK, and a little weaker than LWOTC's SPARK. Both Suppression and the Micro Missile Launcher are included. By default, a Resistance MEC takes 7 days to build in an unmanned Proving Grounds for 20 supplies and 1 Advent MEC Wreck. You'll need the Advent MEC Breakdown research to unlock them.

MEC Archer: The specialized MEC units that Advent fielded in LW2 and LWOTC. Compared to the Resistance MEC, they have less durability and less max damage and crit damage on their main gun, but a bigger magazine on their main gun. More importantly, instead of the standard Micro Missile Launcher, they have a Micro Missile Artillery Launcher which features 3 charges instead of 1, and double the firing range. By default, a MEC Archer takes 8 days to build in an unmanned Proving Grounds for 25 supplies, 1 Advent MEC Wreck, and 1 Elerium Core. You'll need the Advent MEC Breakdown research and EXO Suit research to unlock them.

MEC Pyroclast: A new MEC variant that specializes in close range fire-based combat. They have more durability than the Resistance MEC, but no micro missile launcher or even a standard firearm. Instead, they wield the MEC Flame Projector. It has two firing modes. The standard one is your typical flamethrower, sets fire to terrain and targets. It can be fired this way without ending the turn. The second firing mode, "Phosphorus Meltdown", is different in a number of ways: slightly higher damage, smaller area of effect, it doesn't ignite terrain or targets and it always ends the turn. However, it also shreds one armor, ruptures the targets for 1 point, and deals magnetic-based damage rather than fire, allowing it to damage anything. Phosphorus Meltdown costs 3 ammo and can be used every other turn. The MEC Pyroclast also has one other ability that can be used every other turn, "Charge Servos". This costs 2 actions and gives you 3 movement-only actions. By default, a MEC Pyroclast takes 14 days to build in an unmanned Proving Ground for 40 supplies, 1 Advent MEC Wreck, 1 Advent Purifier Corpse and 1 Elerium Core. You'll need the Advent MEC Breakdown, Advent Purifier Autopsy, and Gauss Weapons research to unlock them.

Prototype Assault MEC: A MEC variant that carries a shotgun and a shoulder-mounted gatling cannon for versatile engagement ranges. The gatling cannon can be used for AoE attacks, or single-target attacks with the addition of shred and bleed. By default, a Prototype Assault MEC takes 10 days to build in an unmanned Proving Grounds for 40 supplies, 1 Elerium Core, and 1 Advent Assault MEC Wreck. You'll need the Advent Assault MEC Breakdown, Gauss Weapons and EXO Suit researches to unlock them.

Military Assault MEC: A MEC variant that carries a shotgun and a shoulder-mounted gatling cannon for versatile engagement ranges. The gatling cannon can be used for AoE attacks, or single-target attacks with the addition of shred and bleed. Offers more power and durability than the Prototype variant, as well as the Close Combat Reflex ability. By default, a Military Assault MEC takes 12 days to build in an unmanned Proving Grounds for 60 supplies, 2 Elerium Cores, and 1 Advent Assault MEC Wreck. You'll need the Advent Assault MEC Breakdown, Heavy Plasma and WAR Suit researches to unlock them.

Frost MEC: A MEC variant that excels at controlling the enemy via bitterfrost effects. Its cannon and micro missiles inflict bitterfrost on hits. Additionally, the Frost MEC has the Chilling Suppression ability for reliable bitterfrost application without needing to roll any dice, as well as the Impact Compensation ability for survival. They are immune to frost, poison, Chryssalid poison and knockback, but unlike most robots are NOT immune to fire. You need the Bitterfrost Protocol research and Advent MEC Breakdown to unlock them. Building one costs 25 Supplies, 5 Cryolite and 1 Advent MEC Wreck, and takes 9 days in an unmanned Proving Grounds.

Frost Droid: A humanoid robot that can equip many kinds of human primary weapons. Specifically, they have access to Assault Rifles, SMGs, Shotguns, Cannons, Sniper Rifles, and Chemthrowers. They also have their own unique pistol which inflicts bitterfrost on a hit, and they carry a Bitterfrost Grenade as well. On top of that, their "All-Purpose" ability grants them a pair of abilities in tactical missions, based on which category of primary weapon you give them. Additionally, unlike most robots, they can carry unconscious units, be carried themselves, as well as make use of cover and use Hunker Down if needed. However, they are only as mobile as a MEC and only slightly more durable than a Drone, so think carefully about giving them valuable weapons if there's a risk of losing said weapons in a mission. You need Hybrid Materials and Bitterfrost Protocol researches to unlock them. Building one costs 15 Supplies, 2 Alien Alloys, and 3 Cryolite, and takes 6 days in an unmanned Proving Grounds.

All-Purpose grants these abilities in tactical missions based on the Frost Droid's primary weapon category:

• Assault Rifle: Target Focus and Maim
  
• SMG: Predator and Flush
  
• Shotgun: Impulse and Slug Shot
  
• Cannon: Suppression and Area Suppression
  
• Sniper Rifle: Squadsight and Holo Targeting
  
• Chemthrower: Open Fire and Chemthrower Suppression

Advent Drone: A small, flying robot that can see a little further than most units. Between that and their high mobility, they make great scouts. They have both a short-range two-turn stun and a mid-range shock attack that can disorient, in addition to the ability to repair other robots. Compared to the Spark's repair, this one is weaker and much shorter range, but the Drone's repair can be used indefinitely, limited only by a cooldown. All Drone variants cannot mark supply crates or pick up timed loot, as they are too small and don't have any hands to do those things. By default, an Advent Drone takes 5 days to build in an unmanned Proving Grounds for 10 supplies and 1 Advent Drone Wreck. You'll need the Advent Robotics research (Drone Autopsy) to unlock them.

Hunter Drone: Very similar to the Advent Drone in terms of how it plays, but by default deals about 3 times as much damage with its shock beam, has more health, armor, and defense, and can repair 2 more HP per use of the repair ability. By default, a Hunter Drone takes 7 days to build in an unmanned Proving Grounds for 20 supplies,1 Advent Drone Wreck, and 1 Elerium Core. You'll need the Advent Robotics research (Drone Autopsy), plus the Stun Lancer Autopsy and Advent MEC Breakdown to unlock them.

Enigma Drone: Somewhat similar to the Advent Drone in terms of how it plays, with slight increases in durability, damage, and repair capabilities, plus a substantial increase in defense. They do not have the Stunner ability, and instead come with Phantom, Conceal, Mark Target (the Officer's ability, which by default can now be used without breaking concealment, just like a LW Holotargeter) and Squadsight (which is used with Mark Target only, not shooting). In LWOTC, they can infiltrate a mission even faster than the other Drone variants do. By default, an Enigma Drone takes 8 days to build in an unmanned Proving Grounds for 25 supplies,1 Advent Drone Wreck, 1 Spectre Corpse and 1 Elerium Core. You'll need the Advent Robotics research (Drone Autopsy) plus the Spectre Autopsy to unlock them.

Phase Drone: These play exactly as you know them from Advent Psi Ops, including their signature wall phasing, blaster, Micro Launcher and their ability to mark targets. This version, however, does not need to reload its primary weapon. They're intended to replace the Deployable Phase Drone utility item since I find the latter rather unbalanced, especially in the LWOTC setting. By default, a Phase Drone takes 5 days to build in an unmanned Proving Grounds for 10 supplies and 1 Phase Drone Wreck. You'll need the Phase Drone Autopsy to unlock them.

SHIV: Considerably different from their incarnations in other mods, these SHIVs don't rank up and don't have upgradable gear. They do, however, come with their own GREMLIN companion which includes the Aid Protocol and Scanning Protocol abilities by default. By default, a SHIV takes 5 days to build in an unmanned Proving Grounds for 25 supplies. They have no unlock requirements besides the Proving Grounds itself. There are also two new research projects (with Tygan, not the Proving Ground) unlocked at the start of a campaign that each give you a SHIV while explaining where the two of them came from and what you'll need to do to build more. These projects complete instantly and have no cost, but can only be done once each.

Alloy SHIV: In addition to the features of the standard SHIV, the Alloy SHIV has better durability, a Laser Gatling Gun, the Bulwark ability, and the Threat Assessment ability. By default, an Alloy SHIV takes 8 days to build in an unmanned Proving Grounds for 45 supplies, 3 alien alloys and 1 Elerium Dust. You'll need the Plated Armor research and Laser Weapons research to unlock them.

Elerium SHIV: In addition to the features of the Alloy SHIV, the Elerium SHIV has better durability, a Coil Gatling Gun, the Automend Shield ability (renamed version of the SHIV mod's Energy Shield ability, which grants a 3 HP regenerating ablative shield), the Collateral Damage ability, and the Capacitor Discharge ability. By default, an Elerium SHIV takes 11 days to build in an unmanned Proving Grounds for 65 supplies, 5 alien alloys, 3 Elerium Dust and 1 Elerium Core. You'll need the Powered Armor research and Coilguns research to unlock them.