that's what I have for now. More ideas will be appreciated

GEARBEASTS
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2 tanks. 1 screen. 1 winner. A tank-duel game.
Controls:
W- Jump; Jump Jets (in air)
A- move left
S- Activate shield
D- move right
Mouse: move aiming reticle (weapon trajectories follow line drawn between reticle and tank. tank can be moving one way and firing another. tank cannot fire below horizontal, except bombs)
left click- fire weapon/use ability
right click- cycle weapon selection
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HP bar & energy bar
Shield: Absorbs %HP damage (unaffected by armor upgrade) as 2x %Energy until exhausted. Contact damages other shield or tank at 5% HP/ 250 ms.
Jump Jets: Strength will have to be played with. Anyway, column formed by Jump Jets extends 1.5 tank lengths from under tank, with a width of .5 Tank lengths. the column extends to full length @ 3x move speed. Burns 10% energy @ keypress and every 250 ms held.
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Weapons and Abilities are upgradeable. The players start with 10 UG (upgrade) points. The first upgrade cost 1 UGP, the second costs 2. Player can bring 1-4 weapons/abilities (not counting armor) into battle.
Flamethrower: 20% energy @ keypress and every 1 second held. xtends @ 1.5 move speed. Deals 5% HP damage/initial contact and every 250 ms of sustained contact. Button can be held down and flame follows aiming reticle. Extends 1.5 tank lengths/2 TL @ UG1/2.5 TL @ UG2.
Shotgun: 750 ms cooldown. pellets travel at 4x move speed for 2 TL. @ 2 TL, pellets have formed 20 degree arc. Every pellet that hits enemy tank deals 5% hp damage. In the fashion of 10 as a triangular number, non-upgraded shotgun shoots the base 4 pellets/UG1: next layer of 3/UG2: final three.
Mortar: 1 second cooldown. follows parabolic trajectory, aimed at reticle. if reticle is less than 2.5 TL from tank, mortar charge is light: shell travels 1/3 screen length @ 45 degree trajectory. if greater than 2.5 TL, charge is heavy: shell travels 2/3 screen @ 45 degree trajectory. deals 30% HP AOE/UG1: 40%/UG2: 50%
Cannon: deals 10% hp/hit. Travels off screen in straight line @ 3x move speed. Cool down is 750 ms/UG1: 500 ms/UG2: 250 ms.
Bombs: 500 ms cooldown. drop from bottom of tank @ .75 move speed. 20%/UG1: 25%/UG2 30% hp damage if in AOE.
Healing: heal 10% HP after 1 second of buttonpress/ UG1: 15%/ UG2: 20%. 20% energy @ keypress and for each succeeding second.
Blinkdrive. Tank teleports to location of aiming reticle on click, after 500 ms of off-screen time. 60% energy/blink. can travel 1.5 TL/UG1: 2 TL/UG2: 2.5 TL.
Armor: 0/UG1: 10%/UG2: 20% damage reduction, (if shield is down).
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energy restores 5%/second.
damage taken to top of tank deals 1.5 damage. If one tank is on top of another tank, it slides off slowly (if shield is up, it damages tank or shield).
Pressing A or D while in the air with shield activated executes an air dash. 10% energy is spent, tank moves 1 TL @ 4x move speed.
Tanks can jump 2.5 tank lengths directly vertical.