A brief explanation of what this story will generally be about.
A modder was making a Halo mod for a 4x grand strategy game when a lightning strikes his home next thing he know he suddenly found himself in Gundam universe in Universal Century. He also found that he has been implanted with the halo mods he has worked with and can "materialised" them at will.
MC's power basically is gets to summon anything he modded that is Halo themed.
As for why not just being able to summon anything from Halo?
Well there's a few things that just doesn't make sense.
Such as the Railgun will have a Magazine and it's semi-automatic or the Forerunner is reloaded by magazines and not shell by shell! They're forerunner for Christ sake like we have shotguns with magazines now, it's totally BS that the Forerunners can't at least figure out to add a magazine!
Anyways he has made halo mods for some Grand strategy games and FPS games. So he can summon infantry weapons along with ships.
Naturally there's a restriction to this OP power, and that is that he can't summon anything that's living. So no grunt spamming, he can still summon ships but he'll need to find crew for them, also he'll need to train those crew.
AI is not living being so he can summon AI, well it's more like the AIs are already built into the ships he summon.
As a fan of both Franchises I'll try to be as fair as possible when it comes to technology of both universes.
So there will be no Halo stomping as clearly Gundam verse has beam weapons, saying that Halo does have NOVA bombs so that MC wouldn't be slapped around and be too afraid to do anything.
Some areas Halo would superior while others Gundam verse would be better.
Weapons:
Gandamverse has beam weapons and Mobile suits which is a huge edge especially with all the noble armours and gundams.
That is not to say that Halo is entirely lacking as Halo clearly has the better ships (each destroyer had 26 missile pods, each pod has 24 missiles making it 624 missiles per salvo, not to mention the spinal mounted railgun)
Halo Railguns are very powerful as even just dropping a piece of metal would be very destructive not to mention hyper accelerating it to a fraction of the speed of light.
While the Minovsky particle that interferes with communications and electronics that acts pretty much like EMPs, but the UNSC has counters to that.
Such as powerful shieldings that could survive an EMP blast, not to mention UNSC ship are extra solar ship without the Sun's Heliosphere to block out most of the nasty cosmic radiation that would interfere with electronics.
There's also shipboard AI which makes it possible for Halo ships to evade on coming attack in the last second.
In the novels UNSC ships are even capable of dodging Covenant plasm torpedoes at the last fraction of a second.
Also in-terms of engine (discounting FTL engine that UC gundam clearly doesn't have) the UNSC is way a head of them in-terms of speed. The scale in the Gundam verse is mostly lunar orbit as most of the space colonies "orbits" around the Earth.
Shocking isn't it? The Great Zeon empire is within lunar orbit, kinda takes the Air out of "Space for the Spacenoids" thing.
In UNSC terms that's practically the front door, in fact the Keyes loop circled around a planet, meanwhile in the gundams shows it takes quite a while to go around.
--story --
'Wha... what the?' William thought as he looks around finding that he's in a completely different place.
'Where the hell am I?' He thought as he suddenly found himself in a back alley of some sorts.
Obviously he didn't walk here as the last thing he remembered was setting the finishing touches to the Halo rings in his Stellaris mod.
And no he was not drunk aa he's a... nonalcoholic.
Yes, William is a nonalcoholic. Due to certain a certain embarrassing incident in the past that left a dark history, ever since then William has developed a phobia of drinking alcohol. So William is most definitely not drunk last night.
But how else could he get here then? William then examines himself.
'Yup still wearing my loose tank top, shorts and his pair of slippers' he thought as he's wearing the same thing he was wearing last night before he fell asleep in front of his computer monitor.
Suffice to say the current attire shouldn't going out in.
'Well shit' William thought while not as embarrassing as being butt naked but wearing tank to with holes and stains is... kinda embarrassing.
'Probably shouldn't bought a new one' he thought as he poked his finger through the hole.
He wriggles it a bit as he regrets being to lazy and conservative to buy a new one months ago.
'it's fine' 'it's just a hole' 'not that anybody is going to his home anyway' he thought, unfortunately his decision back then finally came back to haunt him.
Fortunately as he was about to accept his fate and march out of the alley in all his glorious ragged clothing, William notices a semi transparent flouting at the corner of his eye.
'What is this?' He wondered
He the takes a closer look and stretch out his hand to touch the screen.
Tap
'It's solid!' William exclaimed as this isn't just an illusion.
'Wait! I know this plot! This is what they call getting isekaied and this semi- transparent screen is his cheat' He thought as isekai is the fad is recently times.
Although the concrete floor and wall around him doesn't look the least bit medieval but he supposed that not everyone can be isekaied to a world of swords and magic.
'Probably all those Japanese salary men got most of the western fantasy worlds.' William somewhat jokingly thought as he somewhat believed that he got isekaied at this point.
Anyway he started fumbling with the interface to see what kind of cheat he has.
' hmm... what's this? ARMA 3, StarWars:Empire at War, Stellaris, Rimworld...' he looks through the list of icons with names of games.
Curiously he Taps on ARMA 3
Tap
Then the screen change now showing a list of stuff.
'What is this?' William thought but then he sees on the top corner of the screen a... what seems to be like filter settings.
Tap
He taps it and selected Thumbnails
The screen changed and the list of items now expanded to include a picture of the item in question.
'Marine 2' he reads one of them with a with the picture of a Halo marine armour.
William then looks at the next one titled 'Marine 2' then to 'Marine 3'...
'Huh these all looks familiar' He thought scrolling through the items.
'!!!!'
He continues on scrolling until he suddenly stops at a particular item.
William stares as he read the description of the item titled "ARC-920"
William then quickly taps on the specs and quickly skims through it.
'!!!'
'Semi-auto... 20 round magazine' he reads it as it finally clicks to William
'Isn't this the Railgun I modded into ARMA 3!?' He exclaimed as he swiftly skim through the items on the list making note of anything that would point to him.
Forerunner shotgun with magazines, Special Pelican model Tart-cart (From glasslands novel), another special Pelican model Bogof...
'Yup these are mine alright' he thought as these models pretty much has his fingerprints all over them.
He then click onto the StarWars: Empire at War and began looking through it.
Most of the UNSC ships is there, some Covenant and the only Forerunner structure available is the Halo' suffice to say he has a along way to go before he finishes his Halo mod.
'Any that's not important now!' He thought as he clicks back to ARMA 3 and typed in on the Search bar.
He types in "Civilian"
And then a list of Civilian clothing appeared before him.
He looks through it until he taps on to one.
Tap
Moments later a set of clothing materialises in front of him and fell to the floor.
He picks it up and puts it on.
'A little loose but it's fine' he thought as he toss his old clothes into the dumpster nearby, before heading out the alley.
Out of they alley
'Where the hell am I?' he wondered as he looks at the entirely unfamiliar city around.
He walks around trying figure out where he is, fortunately judging by the conversations around the people there seems to be speaking English... well with a bit of a funny accent.
(It's like how those old black and white films has a completely different accent then it is today even if they're at the same location. It's like every narrator back then is Captain Kirk)
"Excuse me where am I?" He asked a random pedestrian.
"Ahh mate you're in downtown, Sidney " the man replied with a funny sound Austrian accent.
'As if the regular Australian accent isn't already funny enough' William rolled his eyes at the accent.
"Thank man" he replies as he continues to walk around.
William is pretty sure now that like he suspected he got isekaied as he is almost certain that Australia while having the land area of the United States but it has only a population of 25 million, shouldn't have this many sky scrapers.
William glances at the rows upon rows of tall tall buildings, that seems very much out of place with the Australia in his mind, that being a large barren wasteland filled with dangerous animals where people wrestle with Crocodiles and children rides Kangaroos to school.
William's thoughts is interrupted how by an emergency broadcast from the TVs by a nearby TV electronics store.
"We interrupts this program with an emergency broadcast"
That got William's attention as he quickly turns his head to watch the on going broadcast.
"The Principality of Zeon just declared war on the Earth Federation..." the announcer said as footage of a purple haired man (Gihren Zabi) making a speech and crowds cheer while chanting "Sieg Zeon!"
"Well shit" William muttered