Changelog for Update 99 (added 08 November 2019) - Part I:

Features
- Area/weapon/mutation seeding is now far more consistent.
- There's now an option for borderless fullscreen on Windows (Alt+Shift+Enter / in options).
- There's now a confirmation dialog when exiting/restarting a run; R confirms in it.
- Safe spawns now work consistently.
- Added a setting for native cursors - when supported, this gets rid of mouse lag once and for all.
- Added a setting for mouselock (when available) - for windowed or multi-screen setups.
- Both players can now play the same character in coop without making use of bugs.
- Added localization support (see lang-example.ini / copy to lang.ini for translating)
- Almost too many bugfixes.

Balancing
- Weapons returned by Determination no longer have cooldown of last seen weapon in that slot.
- Trying to pause mid-generation now pauses as soon as loading finishes.
- Game now auto-pauses if connection is lost to the in-use gamepad.
- Grenades no long persist on level change (since they could break generation / kill you).
- Proto statues no longer keep rads from previous encounter if forgotten
- Discs now have an axis-aligned bounding box and bounce a little more predictably. (don't get too excited - the spread is still there and you'll still hit yourself a lot)
- Player' plasma shots now hit players with iframe rules when reflected.
- IDPD grenades now harm IDPD (alongside everyone else) if deflected.
- Mimics are no longer multiplied on loops.
- Select enemies now just don't increment kill count instead of reducing it by 1.
- You can now blow up the last enemy with Melting's Ultra A (the trick: it'll leave a corpse).
- Proto chest now defaults to rusty revolver if it's weapon is gone.
- Jungle now consistently offers new mutations on each visit.
- You no longer accidentally pick up weapons when entering secret areas via objects.
- Weapons can no longer end up under $$$-specific prop.
- Hyper Crystal now clears additional area upon noticing the player.
- Ravens no longer lift up and land on same spot if there's nowhere to fly.
- Giving up crown of destiny no longer can cause you to have -1 mutation points.
- Rads should now get stuck on wall edges slightly less often now.
- The game will take minor effort not to spawn the player right on top of cars/generators.
- IDPD explosions appearing on one spot no longer stack horizontally.
- In a particular location, other cars no longer explode when using one of them.
- Elite inspectors no longer pull non-moving projectiles.
- Maggot spawns can no longer be duplicated on loops.
- Enemy' slugs will no longer hit things while on last (almost gone) frames of animation.
- Frog can now use Hammerhead mutation - use active ability when standing next to a wall.

Fixes
- Fixed original weapon gaining cooldown of what last was in your secondary slot when picking up a new weapon while having only one (mostly affected only Chicken and Robot).
- Fixed portal not opening until van is gone if Big Dog and van are the last enemies on the level.
- Fixed automatic weapons/abilities being used when unpausing via Continue/ability button.
- Fixed necromancers trying to revive things that they can't revive (such as boss' corpses).
- Fixed necromancers not doing anything if the nearest corpse has no line of sight to it.
- Fixed a broken torch with T1 collision box behind T1 if dealing >1K damage to it during intro.
- Fixed grenades getting blown up in portal proximity few frames after opening.
- Fixed a number of oddities with Skeleton<->Melting changes.
- Fixed it being problematic to sit down on 7-3/HQ3 sometimes.
- Fixed portals in HQ not opening chests.
- Fixed IDPD freaks being able to freely leave 0-1.
- Fixed Rogue sometimes getting a rad canister on 7-3 with Open Mind.
- Fixed Crown of Love not applying to chests on 7-3.
- Fixed it being possible to farm kills by going between a level and HQ.
- Fixed some tiles being slippery when fighting guardians in 5-2 vault.
- Fixed a very occasional out-of-level hole appearing together with a hostile Horror.
- Fixed cluster spawns breaking through safe spawn walls sometimes.
- Fixed ultra bolts vanishing when out of 0-1
- Fixed it being possible to farm rads by killing-reviving Horror in coop.
- Fixed IDPD plasma ignoring iframes completely, as result dealing ~120 damage per second. It's now only almost always an insta-kill.
- Fixed ravens duplicating if killed just as they are about to liftoff.
- Fixed cars duplicating if grabbed by a snowbot just as they are about to explode.
- Fixed it being possible to force self to deal with a van by blowing up the last corpse around.
- Fixed Gun Warrant not allowing to use "infinite ammo" if clip is empty.
- Fixed blood weapon "exchanging" not working for Steroids' active.
- Fixed vans being required to destroy before a portal can open at 1-1 1-2.
- Fixed proto chest jumping around if pulled onto the crown pedestal.
- Fixed jungle flower not spawning sometimes.
- Fixed certain 2-1 specific props not spawning sometimes.
- Fixed Technomancer spawning turrets outside of the level.
- Fixed a possibility of getting multiple 101-1 portals on loops.
- Fixed ultra bolts skipping enemies/walls sometimes.
- Fixed elite enemy spawn condition not being checked for each enemy separately when duplicating.
- Fixed "spawned" enemies (green rats, nest maggots) not getting killed upon entering secrets.
- Fixed Horror's Meltdown allowing to "reroll" any extra mutations due to some real old code.
- Fixed it being possible to pick up invisible weapons while in portal sometimes.
- Fixed big rads charging the statues only by 1 rad.
- Fixed 5-1 special prop sometimes getting destroyed by enemies on loops.
- Fixed laser and lightning crystals freely moving for a few frames if hit mid-charge.
- Fixed Lil Hunter extremely occasionally dying during spawn phase.
- Fixed weapons not being swappable during boss intros.
- Fixed it being possible to get free ammo via YV Ultra B when having no rads.
- Fixed IDPD portals spawning on top of the player without intending to.
- Fixed elite shielders telefragging the player sometimes (and generally teleporting oddly).
- Fixed golden cars still occasionally being amiss on 3-1.
- Fixed assassins not getting killed on special level transitions.
- Fixed quick restart in hard mode not incrementing hardmode runs statistic.
- Fixed "pop pop upgrade" not being free in terms of rad cost on ultra weapons.
- Fixed explosions and enemy flak-type projectiles not being cleared when a portal opens.
- Fixed it being possible to destroy throne columns with SPC/other wall clearing weapons before starting the fight.
- Fixed lightning weapons not working correctly at 0-1 boss fight.
- Fixed rogue strike canisters being replaced by rad canisters if a big weapon chest spawns.
- Fixed statues absorbing rads even before activation.
- Fixed weapons sometimes rapidly flying off in a direction because of appearing at the same spot.
- Fixed weapon pickup mask being slightly off-center.
- Fixed a rare crash related to elite shielder.
- Fixed 6-1' stationary enemies spawning under 6-1 L1+ boss sometimes.
- Fixed 7-3 and 0-1 bosses not dropping rads that were beamed into them.
- Fixed a rare softlock in 7-x enemy teleportation.
- Fixed "cursed"/glitched crown vaults (where non-guardian enemies would spawn inside).
- Fixed portals sometimes appearing at position of last exploded barrel on 1-x.
- Fixed Frog being unable to turn around when providing an opposite-to-moving-direction inputs.
- Fixed elite shielder's teleport not working correctly.
- Fixed a bug with specific prop unintentionally exploding after hitting it with an energy screwdriver and laser brain mutation.
- Fixed a rare softlock in raven flight algorithm.
- Fixed hyper launcher and hyper slugger hitting allies.
- Fixed a very rare bug with portals spawning off-level.
- Fixed portals spawning at an unnecessary offset from the last killed enemy.
- Fixed a rare crash on dying to CrownGuardian.

Changelog for Update 99 (added 08 November 2019) - Part II:

Misc
- Swap button now switches skins on daily, for lack of any other function.
- Weekly' tooltip now shows the name of the weapon in case you've no idea.
- Health chests now have a separate sprite when dropping from enemies with Confiscate in 2-?.
- Added a potential fix for music playing for a split second even if muted.
- Controls menu now knows more button names.
- Controls menu now waits until newly bound button is released to avoid triggering it's effect.
- Reworked formatted text drawing for performance and locale features.
- Holes inside 0-1 level are now a little darker for contrast.
- IDPD chests no longer appear to be regular large chests with Steroids' Ultra B.
- Proto chest now displays under the weapon(s).
- Names on daily/weekly boards are now shown to best extent.
- The game now randomly cleans up some of smoke/dust/debris if there's enough to lag the game.
- HUD now draws on top of mutation bar in case of too many mutations.
- Control menu' items can now be triggered with Enter (accept-key).
- Regular secondary weapons now draw with outlines during boss intros (b/c black background).
- Secondary weapon' outline now draws on 7-3 for ease of identification on screenshots.
- Van portals now display over most other enemies and effects (as they're a larger threat).
- Pickup prompt now shows the correct key name if it's not E.
- Crowns can now be picked with digit keys (like mutations/ultra mutations).
- Snowbots now have a separate sprite for holding red cars.
- Positional audio ("3d sound") can be disabled in audio options.
- Rusty revolver now has a separate sprite for loadout (thanks to BioOnPC).
- Most sounds can no longer restart more than once per frame, which helps performance.
- Large-scale wall destruction now lags less.
- Freeze frames now have decaying effect when stacking up too much (i.e. no 1s worth of FF).
- Settings are now saved right upon exiting the options menu in-game (to avoid loss of changes).
- Allies dying after portal opens should be a bit less laggy now.
- Grenades no longer make continuous sounds if hit near walls.
- 3-3 boss music now ends after it explodes.
- Captions are now shown for the nearest weapon, not for all nearby weapons. This is also guaranteed to be the weapon that you'll pick up on key press.

Co-op
- Coop-specific fixes and improvements:
- If Chicken didn't find a health pickup on time in coop and was revived by other player, max health is no longer further reduced by 2.
- Fixed the game only checking if one (random) player has low health for health chest spawn.
- Swords & guitars now drop even if the according L1 level was skipped.
- Fixed rads not being attracted to a non-Horror player during beam use.
- Unsuspecting players now cannot be hurt by Frog "not holding it" during level loading.
- Fixed a player being stripped of Rhino Skin passive if they were fainted when it was picked.
- Mutation bar no longer displays under mutation buttons in coop.
- Players can no longer attempt revival of coop partners while at 0 health.
- Health chests can now restore maximum health to both players at once if they are Chicken.
- Rogue' ammo is now preserved upon reviving.
- Hammerhead uses left are now preserved upon reviving.
- "mutation bar" now displays the coop ultra mutations.
- If one of the players is YV, you now get the expected one-time effect on level ultra.
- P2 can now skip credits as well.
- Fixed Horror' passive having no effect on coop mutation choice with Crown of Destiny.
- Coop HUD no longer has duplicate elements for P2.
- Item drops now consider both players in calculations.
- Fixed Crown of Death' effect wearing off upon revival.
- Fixed "Eagle Eyes" bonus wearing off upon revival.
- Fixed camera looking at nothing if your Chicken's (missing) head gets exploded.
- Bloodlust/lucky shot now proc simultaneously for both players with the according "bond" mutation.
- Robot' passive now works consistently in coop.
- Fixed Strong Spirit recovering only for one player per level.
- Players now will automatically pick up their weapons upon revival, provided that they are still lying nearby.
- Fixed extra feet speed boost wearing off after a player dies.
- Fixed it being possible to pick wrong mutation in coop when both players are actively mouseovering them.
- The game now displays a separate kind of HUD for fainted players.
- Fixed Melting sometimes getting 3/2 HP upon revival.
- Fixed discs starting to hurt one of the players in coop earlier than the other.
- Fixed chests and crowns not always playing the touching player' sounds in coop.
- Fixed wrong line 2 color in Throne Butt description in coop.
- Fixed proto chests closing only by proximity towards one of the players in coop.
- Fixed player-race-specific alternate soundtracks not always triggering in coop.
- Fixed area-specific player sounds playing only for one of the players in coop.
- Fixed ammo pickups getting cursed only based on one player's actions.
- Fixed shovel/ultra shovel precision based on one player's stats in coop.
- All of the players are now shown on loading screens.
- Fixed various skills and effects only displaying above one player in coop.
- (Bloodlust, Horror TB, Laser Brain, Level up, Robot' active, Steroids TB, Strong Spirit, weapon switch)
- Fixed Rogue' chests not always appearing in coop.
- Fixed Rogue not always causing the additional enemies to spawn.
- Fixed Melting' passive not always working in coop.
- Fixed weapons not always uncursing correctly in coop.
- Fixed gas TB effect not always working in coop.
- Fixed Rebel-specific sound on 1-3 victory not always playing in coop.
- Fixed Horror' passive not always working in coop.
- Fixed Y.V. specific loading screen text not always appearing.
- Fixed maggot canisters not checking appearance condition correctly in coop.
- Fixed big maggots only attempting to ambush one of the players in coop.
- Fixed 2-1 exploding enemies not always making the "approaching" sound in coop.
- Fixed 2-1 L1+ boss item drop condition not always working in coop.
- Fixed 4-1 entrance condition not always working in coop (now requires any player to meet the condition)
- Fixed 5-3 boss being biased towards terrorizing one of the players in coop.
- Fixed 6-1 exploding enemies only desiring to explode near one of the players in coop.
- Fixed 6-1 stationary enemies only being triggered by one of the players in coop.
- Fixed 6-1 L1+ boss not necessarily tracking the right player.
- Fixed 7-3 boss being only activateable by one of the players in coop.
- Fixed 7-3 boss only being interested in walking towards one of the players. If you had situations where one of the players was randomly ran over by the boss, that's what it was.
- Fixed vans being biased towards running over one player in coop.
- Timer now displays in bottom-left corner of the screen in coop.
- Fixed timer going faster than usual in coop.
- Fainted players now carry over to the next level as you could expect them to.
- Fainted players now emit a small amount of light in dark levels.
- Fixed wasting health on reviving characters with less maximum health.
- Fixed "Bloodlust" proc not working correctly in coop.
- Fixed "Recycle Gland" resetting P2's bullet ammo.
- Fixed Fish' passive working only at P1 slot.
- You can now switch to B-skin in coop by using "swap" key on character select screen.
- Fixed "Trigger Fingers" mutation' effect in coop.
- Fixed "Rhino Skin" mutation' effect wearing off after respawn.


Standalone installer updated: gog-1 ⇒ u99.

who would have ever thought this would happen

I'm very surprised as well. Better late than never, though!

So is the game now fully updated?
If so i might finally buy it

Why does the in-game version say 99r2? isn't the latest version supposed to be 99r1?