YMMV / Master of Orion

• Broken Base: Opinions on the reboot vary wildly. Many hate it for being essentially the first game with a fresh coat of paint, others love it for the same reason and for balancing the races, and others are in the middle. One thing all fans can agree on though is that it is a considerable improvement over Master Of Orion 3.
• Demonic Spiders:
  • If you let the Psilons develop unopposed, they will climb the tech tree. This is usually followed, at some point, by them climbing all over you, guns a-blazing.
  • In the original game, Silicoids, especially in smaller galaxies. They could colonize any planet right from the start, meaning that in small-size galaxies they could literally take over half the galaxy before the other races got the technology to colonize (or invade) planets with bad environments. And of course more planets = more population = more industry = more research = better ships.
• Fan Nickname: "MoO: BaA" - Master of Orion II: Battle at Antares.
• Fanon Discontinuity: The third game. This included a LOT of backstory that had never been hinted at in the previous games and never mattered in this entry either.
• Game-Breaker:
  • Plenty of them, but outstanding is the Phasing Cloak-Time Warp Facilitator combination, abuse of which leads to ships that can wipe out the Antaran Fleet, solo, several times over. Of course, by the time you get all this technology, you've already pretty much won the game anyhow.
  • There's also the "Orion Globe" design in MoO2, a Death Star-sized battleship that forgoes the typical Stellar Converter for a combination of scanning equipment and refined weaponry that allows it to shear through all forms of shields, armour and defences, wiping out whole fleets in a number of turns.
  • The Psilons in MoO 2, if AI controlled. They have huge bonuses to scientific research speed, and gain automatic access to every technology in the game rather than having to pick and choose useful techs from a catalogue of options based on the situations they encounter. As a result, by the middle of a long game an unmolested Psilon empire can expect to be unambiguously more powerful than any rival empire, and by late in that same game, the Psilons can expect to have grown so overwhelmingly powerful that they can effortlessly defeat even alliances of all their rivals.
  • The Psilons in MoO 1, full stop. While they don't get access to all technologies, they do get a huge research bonus (their racial bonus plus their "Good" research rating in all fields effectively amount to a 75% bonus). Therefore, unless they get ganged up on early or have a very poor starting position, they will quickly get a technological lead on all the other races, in all fields, which will grow as time goes by. If left alone, they'll end up out-shooting the Mrrshan, outmaneuvering the Alkari, out-spying the Darloks, outfighting the Bulrathi in ground combat, out-producing the Klackons...
  • Custom races could pick relatively minor flaws that technology would eventually render harmless to pick up loads of superpowered skills, but the greatest gamebreaking trait for them was Creative. This gave you the Psilon advantage of picking up every possible application from a scientific advancement. Even without the fast research bonuses the Psilons have, Creative is absurdly powerful. And custom races had nothing to prevent them from picking up those research bonuses; a lot of optimized race builds for MoO2 were basically "Psilon 2.0".
  • Silicoids are this in small galaxies. They are extremely good at early-game expansion because they can immediately colonize planets with hostile environments and don't have to worry about pollution. In other words, they can more than make up for their disadvantages in population growth and technology by simply taking over far more planets than anyone else, including those with the best industrial bonuses (which usually have hostile environments). However, their advantages will gradually shrink over time as the other races develop new technologies, but their disadvantages won't go away, which is why they aren't quite as powerful in larger galaxies.
• Goddamned Bats:
  • If there are Darloks on the map, you will get constantly framed for espionage against other factions.
  • In the 2016 reboot, Space Pirates represent absolutely no threat to anything with guns and mindlessly charge into anything they see, but their tendency to respawn anywhere an empire doesn't have active sensors means they're a menace to your scouting efforts. They also like to camp at the end of long warp jumps so that they aren't visible until several scouts have started the jump and can't turn back.
• Good Bad Bugs: In the first game, the "nuclear accident" random event will permanently reduce one of your planets' maximum population, fill it to the brim with waste, and change its climate to Radiated. This can be devastating if it had a high population, and was being used for research or production. However, if you have Atmospheric Terraforming and Advanced Soil Enrichment, it actually increases said planet's population cap. A planet that started the game with a max population of 100 (such as all races' starting planets) can hit 300 with this combination plus Complete Terraforming, making it a production powerhouse.
• Nightmare Fuel:
  • The Antarans. Seriously, you'll be watching over your empire, minding your own business. Next thing you know, the music changes to an ominous tune, and Space-Cthulhu is in your face, giving you a heads up before ravaging a colony.
  • The space amoeba. Sure, it looks stupid and most of the time its just harmlessly floating around impeding your attempts to colonize other planets. But then it actually attacks. Big whup, what permanent damage could it... oh god, it ATE the PLANET?! Whole?! (It destroys buildings and population, and renders the planet permanently Toxic.)
• Obvious Beta: The third game was released with many bugs, and in spite of multiple patches issued to try to fix it there were still issues that could impair gameplay. The game is more or less playable now, after many official and unofficial patches, but it's considered "too little too late" by most fans.
• Serial Numbers Filed Off: The mobile game Starbase Orion is essentially MoO 2 with a fresh (and thin) coat of paint. Not that anyone is complaining.
  • Likewise, "Remnants Of The Precursors" is basically MoO 1 remade with modern graphics, a more expansive soundtrack, and a number of quality of life improvements.
• That One Boss: The Crystal Life Form from the first game, sort of. Triggered by a random event, it could appear anywhere and anytime. If you didn't have a big, heavily armed fleet of Large or Huge ships armed with not-missiles? Hope it doesn't approach your territory. Or appear right inside it.
• They Wasted a Perfectly Good Plot: The backstory added in 3 is actually pretty good, and includes a number of good ideas and motivations for the various races as well as a major universal foe that the Antarans themselves are terrified of. Pity the actual game totally ignored it beyond a few leader characters.

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