Shella Snail:
Space Attack: Shella Snail’s space attack is a projectile heart that deals 4 damage. The heart projectile is fast, but has moderate endlag and minimal shield damage. This attack has 2 variants, The standard variant is fast, but the alternate version is much faster, and can be used by inputting Backward (hold until you see hearts emit from your character), Forward + Attack. This attack is exceptionally useful to pressure your opponent into gaining distance or dealing chip damage after combos, as it is far too risky to use in close range for its low reward.
Dash Attack: Shella Snail’s dash attack is a moving shell spin that deals a total of 12 damage. The dash attack does moderate shield damage, and takes a bit to start up, but makes a good combo finisher and can gain ground. It also works well as a threat to your opponent simply by dashing, as the attack animation is identical to the standard dash until the spikes that actually deal damage appear.
Crouch Attack: Shella Snail’s crouch attack is a low jab that deals 9 damage. The crouch attack does low shield damage, and has a long windup, but decently long range, the total animation length of the crouch attack is long enough for your opponent to block, but you can easily mix up into another attack such as a dash or air attack to catch them off guard. The most consistent combo I've found when starting with a Crouch attack is Crouch, Dash, Space for a modest 25 dmg.
Up Attack: Shella Snail’s up attack is a high stab that deals 4 damage. The up attack deals low shield damage, but makes an excellent combo extender, as it has a very short startup, and can easily be followed up by a dash attack. The Up attack has 2 variants, a standard version that does 4 damage and knocks the opponent into the air, but the variant does 16 damage and stuns your opponent briefly, that can be used by inputting Down (hold for a second), Up + Attack. The alternate attack is incredibly effective to punish your opponents while they attack your shield, and can occasionally be used to attack people high in the air. My personal most consistent combo with the up attack is Air, Up, Dash, Space, which deals a total of 27 damage.
Air attack: Shella Snail’s air attack is a downward poke that deals 12 damage. The Air attack does moderate shield damage, and primarily makes for a combo starter/extender, which can easily follow up into most other attacks, with very low endlag. I have personally found it possible to make an extensive untrue combo by using Air, Crouch, then jumping forward to gain distance and attempt to repeat the loop, being able to end it with a dash attack for potentially massive damage.
Super Attack: Shella Snail’s Super attack is a triple lightning strike in front of your character, dealing 20 damage for each strike (note that you can only hit one of the strikes as the hitboxes are coded to only let you hit one). The Super attack has the unique attribute of stunning the opponent for a very long time, giving you plenty of time to prepare any attack you wish to use, with the variant up attack being the most consistently useful, as its preparation time is entirely invalidated letting you use any combo desired.
Tips and Tricks: Shella snail is the character with the single slowest walkspeed (other than happy but that is a unique circumstance) and thus will be caught in a corner frequently, especially if you use the variant heart projectile. Shella snail benefits from dashing more than any other character, and I've found it can be taken a step further, if you dash and then jump you will retain the momentum gained while airborne and able to use Air attacks. To take it one step further you are able to jump in the opposite direction you dashed in and retain the increased speed, to cause massive mix ups and make the snail monster one of the most agile in the game. This is a technique I will call “Dash-Jumping”