In Super Smash Bros. Melee
Megavitamins are similar to Mario's Fireballs in that they are a medium-short-ranged projectile that bounces along the ground. However, they bounce higher, fall faster, do more damage (8%), and have distinctive sound effects from the original Dr. Mario upon firing, bouncing, and hitting; despite being a physical pill as opposed to a ball of flame, they can still be absorbed. They are also used in Dr. Mario's taunt in Melee, in which he tosses a non-damaging Megavitamin up and catches it. The color of each Megavitamin produced (each half can be red, yellow, or blue) is random and has no gameplay effect.
In Super Smash Bros. 4
Megavitamins return in Super Smash Bros. 4. They have been given a major damage nerf, only dealing 4-6% damage, but otherwise, remain relatively unchanged. They also appear in Dr. Mario's side taunt, which is his taunt from Melee, in which Dr. Mario tosses a non-damaging Megavitamin up and catches it. They received a slight buff as well; the game also now recognizes Megavitamins as physical projectiles, so they cannot be absorbed.
In Super Smash Bros. Ultimate
Megavitamins are relatively unchanged from their appearance in Smash 4 with one exception. The major change the move had was the change of its angle from the sakurai angle to a more vertical angle. This prevents the move from locking but gives it potential follow ups.
Special Move customization was added in Super Smash Bros. 4. These are the variations:
These customs share similar attributes to Mario's custom neutral specials, Fast Fireball and Fire Orb.
In Dr. Mario, Megavitamins were used to eliminate viruses. When the player lines up four vitamins and/or viruses of the same color, the vitamins and the viruses are destroyed. In most Dr. Mario games, they appear in three colors; red, blue and yellow.