The Showstopper would upgrade from sniper at level 30. Instead of firing bullets, it now fires(red) acute triangle shots. Its gun barrel becomes extremely thin and long, representing a syringe. Reload is set to zero and is replaced with syringe time(I'll explain later), movement speed is debuffed, damage is set to three, penetration goes up by ten bars and bullet speed is increased. In team dm or any team mode hitting your own teamates heals them. Shooting your enemies freezes them for a set amount of time depending on syringe time. Penetration only affects shapes as shots freeze onto enemies instead of constantly dealing damge.
The Mega Stopper, one of the many level 45 upgrades, would fire giant red dorito shots. Damage is now set to 5, penetration goes up, bullet speed down and syringe time down.
The SkillStopper is a showstopper that fires at -7 reload, 4 damage, +30 penetration(as i said before, this only affects it destroying and passing by shapes) and +20 bullet speed. You have to use skill and precision in order to kill as on the SkillStopper shots fired on a tank frozen by you will take all of the penetration damage as well. However, to even get 2 hits in is almost impossible and can only be done by the best players as that would mean having to shoot two shots directly at the target(reload is way low you you would have to get up close to make sure your shot hits).
That's all from me for now. Thanks!