Version 3.5.1 Changes:

• Minor bug fixes and localization fixes
  
• Reduced mission risk of infiltrate colony, sabotage, and contaminate
  
• Removed AI credits bonuses from all difficulty settings above normal due to the discovery that they aren't being applied correctly and result in miscalculations in AI spending (it makes the AI worse). UCP's next update will fix this, so the compatibility mod has the bonuses restored.
  
• UCP compatibility mod: Reduced MIRV splitting distance back to original amount since UCP now doesn't boost the range of PD weapons for planet defenses.
  
• Removed mind control from Elerians because they won't use it and get stuck in invading. UCP corrects this, so it's restored in the compatibility mod. Elerians get other bonuses without UCP instead.

Fixed a minor error.

Version 3.5:

• All orbital defenses now get the same range boost that star bases get.
  
• MIRV missile splitting distance increased to 32, which should make them split before they get in range of orbital defense PD weapons.
  
• Added several new galaxy types of various sizes and configurations. For details see this post. Please report any issues in generating galaxies including exact seed number and other starting options. If a galaxy fails to generate, you may get it to work with another attempt using a different seed.

Version 3.4 Changes:

• This version of 5X has been optimized to run without UCP. To that end, the bugged missile mods (fast, eccm, heavy armor) have been disabled, rangemaster targeting unit (which is bugged) has been removed, the AI will no longer put stellar converter, blackhole generator, or energy absorber on their ships, and fighters come in groups of 5. If you are using UCP, please use this addon which optimizes 5X for use with UCP.
  
• Black hole generator space and cost reduced
  
• Automated repair unit now takes the same space/cost on all ship sizes. Previously it was very expensive on large ships, but you could just make a bunch of cheap frigates with it to keep your entire fleet repaired.
  
• Corrected the description for Bulrathi uber race trait to reflect the changed bonuses in v3.3
  
• Increased biome tolerance by 5 for terran (now 30), arid (25), and swamp (25).
  
• Credits bonus perk changed to increments of 25%

Updated Spanish and Czech localization. Czech localization is now mostly complete.

Hotfix to fix small bug where evolving technologies reverted to its original position in the tech tree.

Version 3.3 Changes:

• Fixed dragon not using its fighter bays ever.
  
• Added minor rifle improvements to each hyper advanced chemistry node. Previously that node was the weakest of the 5 in terms of usefulness.
  
• Reorganized some of the mod file contents. This is a backend change only.
  
• Added two new starting ages: Microlite Construction and Multistate insulator. Similar to the lopsided starting age, you get all of the techs up to those respective tech nodes but nothing else beyond the pre-warp techs.
  
• Adjusted tiny spiral and small spiral galaxy generation for better star distribution and to fix occassions where the galaxy would not generate as many stars as it should
  
• Planets now degrade due to pollution 1 turn after hitting the pollution limit
  
• Antarans now send a minimum fleet of 2 frigates (previously 1)
  
• Added a partial Czech translation by Frost_DeatH. Hopefully to be eventually completed.
  
• Shifted all techs in the tree to the right so Extreminate no longer overlaps with the UI thing on the left (Credit to Frost_DeatH for doing this)
  
• Adjusted Antarans a bit. Their titans and doomstars now use quantum missiles to boost their attack power. Now their fleets are allowed to include more destroyers, cruisers, and battleships than were previously allowed. This should allow for more balanced looking fleets rather than 80 titans plus a much smaller number of smaller ships (the quantum missiles should also lower the number of titans you see)
  
• Reduced production cost of Volcanic Cooling
  
• Reduced the effect of planet size on terraforming costs. This means huge planets are a bit cheaper to terraform and tiny planets are a bit more expensive. Applies to uber tranformations/volcanic cooling/Gaia transformations as well.
  
• Bulrathi homeworld building now gives research and population growth, and the uber one gives pollution clean up on top of that. I forgot to change the race perk description (will be fixed in the next update), but the structure description has been updated accordingly.

Version 3.2.0 Changes:

• New toxic condenser mechanics. Each planet gets an amount of cleanup from toxic condensers and advanced toxic condensers specific to that planet's size/richness combination (larger and richer get more cleanup). If a planet is too poor and/or too small, a toxic condenser may not be available for that. TC and ATC now show up in the tech tree for everyone, but there's a tooltip that says you only get it if you have a race with the production bonus.
  
• Removed biospheres entirely from the game. One reason is to reduce the total number of buildings, since there are already a lot of buildings you have to build before a colony is up and running. Another is to slow research a bit. I also felt the food bonus isn't needed given hydroponic farms and all of the other food bonus structures. Early game tech tree adjusted accordingly.
  
• Rebalanced money and maintenance costs. Planetary defenses have had their maintenance reduced (mostly to help the AI who builds them everywhere for no reason) while many more advanced structures have had their maintenance increased. Spaceport now gives +15% colony credits (and +5BC) instead of the +1BC per pop bonus before.
  
• Made more adjustments to ship blueprint templates. Mostly this is just improving AI ship designs here and there, but the player templates have also been improved. Planetary defenses no longer get inertial stabilizer/nullifier since it doesn't make sense for them. Antaran designs adjusted as well.
  
• Reduced benefit from inertial stabilizer/nullifier.
  
• Extended the end of the tech tree to have 5 miniaturization tiers instead of 3. Omnipotence now has 2 parts. This should extend the life of the tech tree quite a bit.
  
• Adjusted research point costs to a more sensible, balanced progression that slows down research in mid and late game. Starting from post warp (100 RP), RP doubles for the next 5 nodes, then 1.5x for the next 5, then x4/3 for the next 5, and x5/4 for the last 5. Pretty nice prime factorizations there methinks.
  
• Reduced diplomatic penalty for stellar converter and bio bombs
  
• Minor adjustments to some AI personalities.
  
• Leaders with morale bonus now give 5% increments instead of 10%.
  
• Added one more rifle upgrade in temporal fields.
  
• Fighters now come in groups of 4 instead of 5 since they're a bit too strong with the upgraded PD weapons and especially if you use Sol's UCP.
  
• Antimissile rocket damage increased to 8. AI will no longer use them for the most part.
  
• Steal mission risk slightly increased. Destabilize risk slightly decreased.
  
• Defeating the Guardian now unlocks two additional technologies: Uber gaia transformation and Orion infrastructure (Orion biome renamed to Uber Gaia). Allows you to transform gaias into the Orion type uber gaia, and the Orion infrastructure (only for uber gaias) grants production and research.
  
• Reduced minor civ level costs for researchers and traders.
  
• Lithovore ultra rich growth rate reduced to 5.
  
• Population growth racial trait changed to 20% increments. Auto repair trait cost reduced to 2.
  
• Meklar now have -25% beam defense and small HW instead of uncreative.
  
• When building a marine barracks, you now start with 1 marine instead of 4, and marines train every 8 turns instead of every 5. Maximum marine count increased to be equal to the planet's population limit instead of 80% of max population.

Version 3.1.0 Changes:

• Removing star gates (Trilarians will get jump gates to start instead), Meklar uber building now gives research instead of the jump connection, slight balance adjustments to a couple other uber buildings. Star fortresses no longer generate jump connection. I was forced to do this in order to fix the long turn processing issue.
  
• Removing erroneous pollution tag from deep core mine and adding missing pollution tag from crust prospecting
  
• Adding to production cost of scientific victory buildings 2 & 3 to give you more time to attack an enemy that's building them as well as to correct a reported issue where the third had a negative industry cost
  
• Removing neutron collider and robo miners from hyper advanced colony ships because they don't work when your colony starts with them. Reduce cost of the ship to 1250.
  
• Increasing particle beam damage to 40, reducing range dissipation. Increasing fusion beam armor piercing to 15, increasing fusion beam range dissipation. Mauler device AP increased to 30 and range slightly increased. Plasma beam range dissipation slightly increased.
  
• Adjusting a few AI ship blueprints for minor improvements
  
• Uber biomes (except inferno) will now have 2 possible biomes they can degrade to when degrading from pollution (the exact biome you get depends on the uber type), and the distance from the uber to the parent star determines which biome. One of the two biomes will be able to transform back to uber directly, wheras if you get the other biome you'll have to terraform once first. Also Ocean planets close to the parent star will now degrade to swamp instead of tundra.
  
• GNN will now continue the "State of the Galaxy" reports further into the game, with the last ranking being given on turn 705 (previously 405). This is particularly useful if you're playing with some victory conditions off and can't see the rankings on the victory screen.
  
• AI will prioritize choosing certain techs that they prefer to use instead of choosing semi-randomly.
  
• Plasma web damage increased and splash area significantly increased (it now matches the animation). Added it to a couple AI blueprints. Give it a try and let me know how well it works.
  
• Lithovore growth rate slightly reduced on rich and ultra rich planets
  
• Removed uncreative from Meklar, gave them -25% beam defense and small homeworld. Ship auto repair cost reduced to 2.
  
• Reduced all toxic condenser types by 5. Added advanced versions of the toxic condenser that you can get by researching the astro biology node. The advanced ones are only for medium and larger planets.

Version 3.0.2 changes:

• Minor civilizations now have 9 levels and have had their costs and rewards adjusted.
  
• Made a slight adjustment to the "neutral" starting bias so you now start at "unease" with the AI. This was to address the fact that if you make a custom race, you start at "neutral" with everyone, which puts you at an advantage vs if you took a stock race.
  
• Made some improvements to ship blueprints, particularly for Antarans. The goal was to get them to have a higher attack rating so they send smaller fleets. Made minor changes to the Antaran settings file as well to help keep fleet size down.
  
• Slight adjustment to Psilon AI to make them build fewer colony ships and more defenses.
  
• Minor bugfixes.