If we go with Tank over Hydro (which, wasn't there a Chaos Emerald or Chao Egg or something located underwater that the Hydro might come in handy for? Don't remember), then the Force Shield is a no-brainer, which only leaves 10 points left. That's either the Flamethrower + Missile Barrage combo, or any one (1) other upgrade. Point Defence wouldn't catch Sonic unless he's already stunned, but might come in handy for some slower animal heroes/any shenanigans Tails tries to pull. A Main Cannon would let the 'bot do large AoE attacks, which have a chance to catch even Sonic if the area's large enough, but has the downside that the entire robot would need to turn to fire it, telegraphing its attacks massively. The Shoulder Cannons would seem to be a middle-ground between the two, slower to target while doing more damage than the Point Defence, smaller AoE and less damage while more nimble than the Main Cannon. The Flamethrower + Missile Barrage gives area denial that can shut down approaches from at least one side close-in, as well as some long-range small AoE spam that's less telegraphed than the Main Cannon while likely travelling slower as a downside.
Does the tank model have anything that can stun Sonic for the PD guns to ventilate him? I mean, the Main Cannon would presumably stun him if it hit close enough, it's just a matter of doing so - plus the fact that Main Cannon + Point Defences + Tank Model leaves no room left for the Force Shield, which I'm pretty sure is a must for survivability to cover the limited areas on it not covered by thick armour from quick exploitation by the hedgehog.
Hmm... for now, I'll stick to one Hover, one Hydro, until someone can let me know if there's anything we'd specifically want the Hydro model for or not.
[X] Plan All-Terrain Badniks
-[X] Delta
--[X] Hydro Model: A heavier variant of the Strider made for underwater combat, this specialization unfortunately leaves the Hydro Model compairitivly slow on land but allows it to move with incredible grace and speed under the water. While not as powerful the Hydra Model terains durabiltiy second only to the Tank Model weather on land or in the water allowing it time to escape back into it's preferred environment when caught out on land. The standard weapons of the Hydra model are it's sheer size and a torpedo launcher. 5 Points.
--[X] Water Laser: A powerful weapon that fires water out as obsene speeds, more powerful than most normal weapons but it needs water to recharge. 5 Points.
--[X] Stealth: The Hydro unit becomes invisible to the naked eye while in water. 10 Points.
--[X] Sonic Blast: The Hydro Model uneleass a powerful pulse of sound at an enemy, naturally it is more powerful under water and nearly useless against Sonic himself on land. 10 Points.
-[X] Epsilon
--[X] Hover Model: Close to the frame Model the Hover Model was recently thought up by the doctor and gives the E=Series using it aerial mobility alongside powerful claws for both attack and defense. 5 Points.
--[X] Energy Blaster: A large Energy Blaster capible of devastating large areas either with a succession of smaller blasts or a charge up larger one. 10 Points.
--[X] Missile Launcher: Launches missiles from the hover units back. 10 Points.
--[X] Forcefield: A rainbow colored forcefield that helps to defend the hover unit from harm. 5 Points.
Never do edits after 2am when you've been up since early morning the previous day.
