Legal Disclaimer: I don't own the rights to either Halo or Mass Effect, own copies of the games, not the rights to sell/make money off of them. The only things in this story that I own are any OC's that show up, and any changes to the Story.

Warnings: This story will contain lots of violence, death, possible lemons/limes, and explosions, also a giant fire berating Turkey if I can figure out how to incorporate it into the story. Parings, if any, are undecided as of now, leaning towards Shep/Harem though. By the way, Male Shepard.

Chapter Disclaimer: just an explanation/rant on why the Council will not stand a chance in this fic.

Damage output comparisons

Destiny Ascension

Main gun length- 1,000 meters

Yield- 60.5 kt per shot; 1.815 mt over the course of a minute

Turrian Dreadnaught

Main gun Length- 700-800 meters

Yield 29 kt per shot; in and around one megaton per minute

UNSC frigate

Main gun length- less than 300 meters

Yield-64.53kt; lengthy reload times

Conclusions, whilst Council ships would Damage UNSC ships given enough time or numbers, the fact that the Destiney Ascension can rip through just about anybody's barriers with one shot indicates that the UNSC would be able to one-hit-kill pretymuch everything smaller than a Council dreadnaught, barriers or no. Meanwhile the council would have to get through the Forerunner based shields on UNSC and Covenant ships, these shields have been recorded surviving multiple MAC rounds without failing, meaning that in order for the council fleets to take out a human or covenant ship a council dreadnaught would have to hammer away at a UNSC/Covenant ship for several minutes without being destroyed its self, or they would have to bring multiple dreadnaughts to bear on a single target in order to breach its shields. The fact that the big three Council races only have 75 dreadnaughts all together at the start of the reaper war, plus the fact that a UNSC fleet totals in at a minimum of 75 ships, equals curbstompng of Council in open war. And anybody who tries to say that the Voulus could help them out or something…WHAT KIND OF SUPPORT COULD A SPIECIES WITH NO MILITARY OF THEIR OWN PROVIDE IN THIS SITUATION. Shure, they could provide the big three with resources to make more ships; but that takes time, time that they just would not have in an ongoing war; and even in peace time, at their normal production levels it took the council races 3 years to add 5 dreadnaughts to their arsenal, with one other having been retired, and this is with humanity stepping up production after gaining a council seat. Now, assuming that plans for the SSV Logan started immediately after Mass Effect One ended, that's still three years from planning to launch, and that three year gap would prove fatal in a war where your very survival hinges on ships like the one your building, remember, it would take concentrated fire from multiple dreadnaughts to destroy a UNSC Cruiser class ship with Forerunner shields in a timely fashion; and whilst the council is concentrating on one ship, the UNSC can destroy the council fleet at their pleasure, and the council would never be able to replace the ships and personal they lose before they were forced into an unconditional surrender. Now even if the big three are able to justify an increase in military spending to their respective governments, in order to stand a chance in a war with the UNSC and the Covies, they would still need to be able to build and crew thousands of dreadnaught-class ships before the conflict started; and they just don't have the people to do that, nor do they have the time to get that many people the old fashioned way (wink wink, nudge nudge).

NOTE 1: the mass-accelerator yields assume they fire rounds the same size as the one mentioned by the alliance sergeant in ME2, although some discrepancies in size are possible, it is unlikely they would be much bigger than the 20 kg size mentioned given the operating principles of the guns in question.

NOTE 2: this also assumes that the former covenant races do not get involved, which they will. Plasma torpedoes and energy projectors will bypass Council Kinetic Barriers.

NOTE 3: this does start about 100 years after the beginning of the Human-Covenant war, so if you factor in all the technological advancements that will have happened in that time, the Council's going to be Fucked if they go to war, and the Batarrians are already dead men walking.

NOTE 4: disrupter torpedoes might be a threat depending on how many of them make it past the point defense guns

NOTE 5: Assuming that the council has the facilities to build 25 Dreadnaughts at a time (come on, that's accounts for over half the Turrian fleet and is around half of what the Salarians and Asari have combined) it would realistically take over 300 years to produce enough ships to be a threat.

NOTE 6: The above note assumes that they could also increase production capacity to replace ships that were decommissioned, and build additional facilities in order to perform the necessary repairs/resupply's/retrofits to existing ships without adversely affecting production, and that they could find the resources to build and fuel the ships in question. Yea, I think I made my point.