Ideas for inventions:
-Better Reactors. Especialy useful for the large replicators. Plasma reactors maybe?
-Forge Ships. With the asteroid miners, this would make a mobile industry. Invaluable for military logistics, uplifting, and fortifying worlds in the orcs path.
-Void Shield Penetrators. Remember those penetration crystals? How they ignore void shields? Stick those on a torpedo. Maybe with Speed also?
-Better Armor. By that I mean both armor material and tanks. We havent improved those yet.
-Artillery. Kings of Battle. Nuff said.
-Mines? Hard to imagine them being very useful in space, but 40K uses them if I remember correctly. Would synergize well with our divination.
-Spaceship Wards. Both for travel and psyker defence.
-An Artefact Boarding Craft. Can you imagine the kind of damage that we can do from the inside of a space hulk? Teleporting through shields is a bitch and a half though.
-Better Comms. Both in general and to never lose our leader bonus on the battlefield. Some sort of artefact helmet at least?
-Deployable Turrets. Or even static ones. Not drones yet though!
Edit: Some drones yes, drone heavy military no. We are not good enough to make those reliable with Chaos around.
-A planetary sensor net. We need a way to detect small groups of orcs so that we can purge them before they grow into armies.
-Antigrav. We are MUCH better at it now. An action to see what we can do with it? Nothing specific, the uses of such are too many to list.
-A Nova Canon. Or some other sort of very long range heavy gun. For sniping space hulks. With penetrator rounds
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-A Precision Orbit-to-Surface Weapon. What it says on the tin. I would prefer that it is called Mjolnir and sends down Rods from God, but whatever works. Both as satelite (for keeping orc numbers down) and for ships.
-A Descent Class Destroyer. Straight from our favorite hellword of Avernus, this is a frigate designed to descent (duh) into the atmosfere from orbit and completely ruin someones day with starship grade weaponry from up close.
-A Continuous Flashbang System. Orcs need eyes and ears to fight I am pretty sure. Should be able to protect our people from it pretty easily, and if need be use the bangs for some sort of a sonar to see with/augument battlefield awereness. In a grenade form probably.
-Tacnet. If we dont have it, we have to make it. Augumented reality helmets, sharing friends and foes locations, marking points of interest, mission objectives, etc. The effects of this cannot be underestimated.
-Fusion Forge. Syphons light gases from gas giants and fuses them into elements which are then used by replicators. Ideally the fusion procces produces power also (for the replicators probably). Might be expensive and not very efficient, but allows for industry in systems without material wealth (or when it runs out). Would probably be VERY hard to invent, but gas giants are everywhere. Also first step towards Star Forges.
Things to keep in mind:
-Orcs are very vulnerable to decapitation strikes.
-We should max out Small Works and equivalents ASAP.
-Remember to touch up on our older inventions from time to time.
-Our shields are a gamechanger. As such, we should rewrite the Big Book of Tactics before the orcs get here. We also need to write the space equivalent of such. And run some mock battles after.
Might edit in some more later.
Edit:
-Medigel
-Train/Build Astropaths.
-Alternative FTL travel/communication method. A long term project. Unlikely to be faster then warp travel, but might not have its weaknesses either. In warp distances are a mess, so two star systems right next to each other might be years of travel apart. Also in-system FTL or FTL munitions would be extremely useful.
-Improve medicine/genetics/juvenenat mass production. For longer lifespans.
-Encourage/improve birthrates?
-IMPROVE EDUCATION! I dont mean through inventions, but by reforming the school system.
-Cultural engeneering. Both for integration rates and to modify cultures to remove stupid and add reason. Do not underestimate the power of Culture. There are places on Earth where people dont lock their doors, because stealing is simply something that is not done. Thats culture at work, and if we can master it, the effect could be ridiculous. A culture is to people what mind/psychology is to an individual.
-Improve Warp Safety and Navigation. Probably with wards/gellar fields and some sort of navigator training and equipment for psykers.
-Prostethics. We are going to have lots of cripples is a few years. Focus on quality of life, cost, and reliability I think. Or cloned limbs?
-Cyberbrains. Long term. Armor the brain and add enough stuff for it to survive without a body for a while along with a Mind-Machine interface. With good enough cybernetics and cloning people will be able to swap bodies without uploading (VERY hard to do in 40K) and we could have infantry made of (almost) full conversion cyborgs. Who can than return back into their flashy bodies.
-Medical Replicators. Can replicators print organs? If not, invent some that can.
-Diggers. Underground warfare might not be a concern now, but one day it wil be. Also dig under enemy army and set of a nuke. Should do some damage.
-Weapons to counter diggers.
-Stealth. Low skills for that right now though.
-Quantum entaglement comms. Unlikely to work without lots of drawbacks (or at all), but we NEED some sort of reliable coms between our planets at the very least.
-Better Void Shields. These are warp tech. We are very good at both warp and tech. Something utilizing our runes, crystals, and powerful psykers maybe?
-Adamant mass protduction improvements. Adamant is bull**** tough, and it is what allows for those multiple km long ships we use. If I remember correctly, its production is extremely difficult and is a major bottleneck for spaceship production.
-Look into anti-boarding tech/tactics/stuff. Orcs like to board ships and are vwery good at it. Dont let them leverage their strengths.
-Under description for Gellar-like crystals it says that a project to enhance Gellar fields is open. This should be done soon.