I've been playing this a lot lately and got annoyed at all the ancient bugs and balance issues. Since I've got a few weeks off work for the holidays I jumped back into the code and made some massive changes.
This game started my professional career as a game dev so coming back five years later to apply what I've learned has been really fun.
Changelog
General
Added more robot flavor text.
Autocastable Active Items now activate when an enemy enters their Tower's Attack Range.
Fast-forward speed in Singleplayer increased from 3 -> 3.5x.
Kills by towers on Hard and Serious difficulty now provide experience to nearby towers like they do on Easy and Normal difficulties.
Easy -> 35% of the kill XP goes to all nearby towers.
Normal -> 25% of the kill XP goes to all nearby towers.
Hard -> 25% of the kill XP is divided among nearby towers.
Serious -> 20% of the kill XP is divided among nearby towers.
Experience from kills reduced by 15%.
Improved Tower Targeting Algorithm:
No longer makes sub-optimal choices sometimes in maps like Strikethrough due to odd path shapes.
Now takes into account Abilities for certain Towers and not just Auto-Attack range.
Star's Active deals more damage than its Auto Attack and is treated as its true "damage range" when Towers are deciding what to attack.
Also applied to the Volcano.
It's possible to enable this for any Tower but not very many can "carry" so I didn't find the experience pleasant when this was applied to Towers that deal a bit of long-range damage but don't murder everything in sight.
Towers that cannot deal Auto-Attack damage (Life Guardian, Alchemical Lab, Support Structure) are treated as having no "damage range."
Fixed these algorithms for Mazing levels as well.
Fixed bug with Mana Motor that could lead to its buff no longer applying.
Fixed Items teleporting back to their slots if a HUD update is triggered while dragging it.
Fixed enemy gibs often not simulating their physics correctly.
Fixed being able to break the game by selling a Tower with a Soul Harvester in its 7th Item Slot when using the Stockpile Specialty.
Fixed the Vacuum noise playing forever if you sell it while it's mid-suck.
Fixed a bug where enemies dying while under the effects of the Cardboard Box Tranquilizer debuff could lead to later enemies having super speed.
Fixed a bug where disconnecting with a Hybrid Artillery Mine on the map could break buffs when you started another match.
Fixed Mana Motor Overdrive always providing 500 Attack Speed.
Fixed enemies/towers/presents failing to highlight when hovered sometimes.
Mazing algorithms for path calculation/targeting sped up significantly.
Massive CPU performance optimizations.
Should see much higher framerates and better frame timings (less stutters) unless you're GPU bound or framerate capped.
Highlighting algorithms optimized for less CPU/GPU usage. Should give a bit of a framerate boost since this effect was quite heavy.
Towers
Added a limit to Kill Bounty Bonus at 50%.
Black Hole Reduction enemy health percentage from 7 -> 4%.
Black Hole Insatiable Mass mana cost from 8 -> 10.
Corpse Flower Damage to DoT from 20 -> 10%.
Guardian Damage to Mana from 1 -> 0.5%.
Guardian Do No Harm no longer considers its own tower when abilities are cast or mana is distributed.
Opportunist Overkill chance from 15 -> 20%.
Prism Tower pathing algorithm fixed so that targeting no longer breaks.
Previously you could get the targeting into a state where it would attack the wrong enemies, ones completely out of range, and create odd paths through towers.
Prism Focus Orb Stun Time Per Tower from 0.5 -> 0.35s.
Prism Network XP Per Bounce from 8 -> 6.
Prism Network Damage Per Bounce from 12+5%/Lvl -> 10+4%/Lvl.
Mana Motor High Compression mana cost from 4 -> 6% per tick.
Moss Engulf Damage Per Second from 140 -> 100.
Oven Sizzle Armor to Damage Multiplier from 0.8 -> 1.
Star Sunbeam now deals 15% Splash Damage in a 200 unit radius.
Star Sunbeam Damage from 125+10/Lvl -> 100+7/Lvl.
Items
Ash of the Scholar autocast now works and will cast itself on the last chosen Tower if it's still in range.
Bonus Fee Kill Bounty Bonus from 14 -> 8%.
Rack Em Up Bounty Bonus from 17 -> 12%.
Deregulator Burst Chance from 15 -> 20%.
Invigorator Buff Chance from 25 -> 40%.
Inhibitor Duration from 8 -> 11s.
Mystic 8-Ball Mana from 3.5 -> 4.5.
Pipe of Clarity Mana Cost from 50 -> 35.
Pipe of Clarity Cooldown from 45 -> 30s.
Pollaxe Armor Reduction Chance from 15 -> 20%.
Combat Syllabus Damage to XP from 1.6 -> 2%.
Tome of Knowledge Bonus XP from 36 -> 32%.
Soul Harvester now gives Mana for kills that occur in its range OR kills by its owner even if they are out of its range.
Specialties
Enraged Attack Speed Bonus from 85 -> 200.
Wizard Mana Bonus from 50 -> 125.
Wizard Mana Regen Bonus from 0.4 -> 0.5.
Hunter changed from 25% Bonus Damage to Bosses to Always Crits Against Bosses.
Hunter no longer has a Crit Multiplier bonus.
Hunter damage penalty to mobs from 15 -> 25%.
Timewinder now also also provides a 0.5s BAT Reduction.
Equalizer now converts all attack and spell damage to be 50% Will and 50% Magic damage.
I left in a bug where you can win and lose at the same time if the very last enemy to leave kills you since I thought it was funny.