Idea 1:
Pros:
Move at normal speed while spun up
On kill: gain +30 ammo
Crits whenever it should Mini-crit

Cons:
+25% slower spin up time
-80% damage to buildings
No Random Critical Hits

Idea 2:
Pros:
Can Shoot down projectiles (If a projectile cannot be airblasted, it cannot be destroyed in this way.
On destroy projectile: Gain +30 ammo

Cons:
-30% firing speed
-30% damage

The name is meteor shower so I was thinking
-50% ammo
-25% firing speed
-only fires out 1 bullet per shot

bullet is a small meteor
+45% damage
+50% spin up time
+25% spinup movment speed
+can shoot down projectiles
(stats might be a bit op or un-op, but my first time making stats for a weapon, dont' hate)

Idea 2 is okay, but a bit underpowered, and Idea 1 makes it an obvious overpowered upgrade from stock, because, let's face it, the Heavy wasn't made for buildings, ya would just send a demoman to do that.

And no, your stats are not OP, Dolphin Protocol, they're rather un-op in fact.
Not hating, just my humble oppinion and advice.

Ok, thanks for the help ;)

Alright, new idea.

Pros:
Can shoot down projectiles (Unless projectile is unable to be airblasted)
On destroy projectile: +50 ammo

Cons:
-20% firing speed
-25% damage penalty

Sparkwire, if you can, you should change the sound

Edit

Shoots rocket-like meteors

Pros

meteors can set people on fire if a direct hit.

Cons

-50% dmg if blast from impact on ground.

Can only shoot 1 at a time. (1/3 sec.)

10 Ammo

Holy crap, mass reduction in minigun firing speed.

Pros:
Can destroy projectiles
Minicrits instead put enemies on fire
+10% firing speed

Cons:
-25% ammo
-5% health
-60% speed while deploying

An item named 'The Crate Smasher', stylized after Half-Life's Crowbar, was commented on, giving stats that'd crash the TF2 market. Just because the name is cool, doesn't mean you need to focus the stats solely on it.

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Valve: Nope. You're getting this with Half-Life 3.

Just an idea
Pros: +50% Movement speed while weilded
Cons: Medic heal rate decreased

New idea


Pros

+70% movement speed while barrel is spinning.

Special Fire: sets whoever gets hit by this on fire and consumes 10 ammo per hit. works for 5 seconds.

Cons

-40% movement speed when barrel is not spinning.

only 150 max ammo