So, with what little time we have left speculating about the plant before it finally takes root, what are your expectations gameplaywise based on what we have seen so far?
Gimmick wise, I feel the pot will be central to it's design and probably will have some unique collision effect to it. I can imagine either some sort of damage reduction or other protective ability around it, kinda like Jr's Clown car, perhaps? Since the Pot is rather small and not a big part of the overall model though, it might not be relevant at all. However, when one thinks of the plant, the motion of ducking into a pipe comes into mind. I believe that is what Sakurai went for with the (probably) Down B move, but seeing that attribute distributed over the model itself would be hilarious! (I mean, some alt skins have the plant drag a pipe around)
Now, the specials look really cool and full of potential to me.
The spike Ball (probably neutral B) can work like an anti-air move to stop aerial approaches from above. In the reveal trailer you actually see Samus dropping in from above, only to dodge away to the side, which can be followed up with the ball immediately. Unfortunately it doesn't look like you can move with the ball out, unlike the Piranha Plants from SMB3. Another thing we do not see is the distance the ball bounces across the floor or it's interactions with other hitboxes.
The poison seems to work as a nice area denial tool. Spitting out a non-knockback DoT cloud can lead to some nice trap set ups and mind games, depending on how damaging it is. Charging it and setting it up seems to be a given to do when the enemy is far away, so prepare to do that a lot for stage presence.
The biggest potential i see for this move lies in it's ability to hopefully get B-reversed or wave bounced. Any way of additional mobility is always highly appreciated and helps us with landing and evasion.
The leaf propeller looks like it gives you full control to steer the Plant either directly up, down, left or right (remember, I take my assumptions only from the footage shown). I hope the leafs from the side have a small hitbox, like K Rool's propeller pack, because carrying people off the side with that move would be utterly hilarious. Otherwise, we see the plant landing with this move in one of the videos, but it's hard to determine the endlag from it. If you see your enemy going for the lower edgeguard, recovering high might actually be viable. We'll have to see...
And of course the big one...the down B, the Pot move itself. Pitanha plants ducks into its pot really fast to activate armour, but the steering seems to take a lot of time. that means you cannot just throw it out without thought against an enemy that, say, crosses you up with an aerial. it just gives them a lot of time to hit you or grab while you are slowly turning around. The move itself seems to be designed as an anti projectile move instead, as firing something usually keeps the target around the same area for a bit, giving you the time to take aim and bite. You can also use it as a ranged option for off-stage play, of course, we'll have to wait and see how useful its going to be overall.
One thing i wanted to say on that note is that i believe the "weird" animation where piranha plant is seen gnawing upwards and downwards, like a plant straight from the original SMB, is what happens if you do not charge and angle the down B at all, as you can watch the animation starting with the plant in the pot, rather than at normal height. If that move would be its up tilt, why start at the pot?
So yeah, those are my expectations/predictions on how the specials will work. I really cannot wait to get my hands on the plant, so please hurry up, Nintendo!