ShapeyWave

How many hits get through before the run ends. A hundred levels deep, and the thing you are still buying a hundred waves from now.

How far out the turret starts working. Fifteen levels take it from 400px to 700, pushing the fight away from you and buying back seconds.

How fast the barrel swings onto its next target, 3.5 up to 9.5 over thirty levels. The difference between tracking a wave and chasing it.

A shield around the base holding one charge a level, up to three. Each charge swallows a hit whole, however big it is, and a spent one comes back every 30 seconds.

Takes a point off every hit that gets through, one a level up to three, never below 1. Contact damage never ramps with the wave, so a point off is worth as much at wave 100 as at wave 10.

Straight damage per shot, half a point at a time. Enemy health starts climbing at wave 20, and the last levels keep the turret ahead of it.

The gap between shots, from four fifths of a second down to a twentieth. Cheapest thing on the board and the biggest jump in output.

One barrel, then two, then a three-round spread. Two levels, priced like the late game they belong to, and they turn a clean line into a cone.

Shots punch through the first shape into whatever is queued behind it, up to three deep. The answer to anything that arrives single file.

Widens the blast that lands with every hit, five levels from 5 out to 30, until the small stuff has stopped being a problem at all.

How fast the shot crosses the gap, fifteen levels from 200px a second up to 1325. Fast enough and the dodgers stop getting out of the way.

A bigger round is a bigger hitbox, twenty levels of it, up to double what you started with. Quiet, cheap, and it never stops paying.

Hits jump to the shapes standing nearest the one you struck. Each level is another point of arc damage, another enemy caught, more reach.

Every hit from the turret sets the shape burning for three seconds, at 1, 2 then 3 damage a second. Hit it again and the fire starts over rather than stacking.

Each hit has a 10% chance, then 20%, to freeze the shape solid for a second: no walking, no weaving, no dashing. A shape that has just thawed cannot be frozen again straight away.

Every hit shoves the shape straight back, 20px and then 40px. It always gets time to walk that ground back before the next shove, so a wave slows down but never stalls.

How hard a shot may bend after the enemy it was fired at. Three levels, a radian a second each, against a barrel that traverses at 3.5.

A ring around the turret that takes a quarter, then half, off the speed of everything inside it. Two levels, the second covering 400px.

Up to five small turrets posted around yours. They keep the fire rate a new save starts with, but hit for half your Damage and borrow your Bullet Speed and Range, so they keep pace with the run. Each one can be told what to aim at.

A ring pulses out from the turret every 8, 6 then 4 seconds, reaching 100, 250 then 400px, and stuns everything it touches for a second. No damage, just time to work through a crowd.

One, two, then three saws circling 140px out, turning faster at every level. They cut whatever they pass for your Damage, right in the last stretch before a shape reaches you.

The turret lobs mines out around itself, one every 6 seconds at first and every 2.5 by level five, up to ten down at once. Each blows under the first shape to step on it, with a bullet blast twice the size.

Rocket pods on the turret fire homing missiles at the toughest shapes in range every 4 seconds. One pod, then two, and each missile hits for double Damage with a blast half again as wide as a bullet leaves.

Every wave you clear patches the turret up, 1, 2 then 3 health a wave, never past its maximum and never in the middle of a fight.

Once a wave, a hit that would end the run leaves the turret on 1 health instead and blasts the ground clear: 150, 250 then 400px out, at 2, 3 then 4 times your Damage. It rearms with the next wave.

Each shape in a wave gets a 2%, 4% then 6% chance to arrive as a Credit Check instead: a harmless target worth 55 credits, with twenty Tanks of health, that bolts after five seconds.

Begin a run on wave 5, 10 or 20 instead of wave 1. Each level goes on sale once your best wave is double the one it opens, and the waves you skip pay nothing.