Previous characters (click to view, Link done by georly)
Disclaimer: I can't read Japanese, so I may have missed certain effects that are hard to test (such as shieldbreaker properties) and I don't know the names of the custom moves so I've completely made them up.
This time, it's Metaknight, who should be completely banned from all tournaments because his custom moves are so broken!
Or not, he got a nerf from his old Brawl days, but I'm not too clued up on certain aspects of his specials in Brawl due to rarely playing him, so I may not have as much information on his changes, more just what we have now.
Neutral Special 1 (Mach Tornado)
Metaknight rapidly spins around, creating a damaging tornado, doing 1% damage a hit and putting you into special fall afterwards.
You can keep tapping B to increases the duration of the move as well as use it to gain height, it lasts about a second at it's shortest and does 8% damage if all hits connect, whereas tapping the button makes it last 2 seconds and can do a total of 22% damage depending on whether all the hits connect and how fast you press the button, but it can do as low as 10% if you tap too slowly.
The last hit does increased vertical knockback, but it's not able to kill Samus until around 180%
Metaknight has reduced control during the move, but he can still use it to get around and it will beat out low-priority moves or projectiles that do low amounts of damage (it will destroy a Homing Missile but not a Super Missile).
Neutral Special 2 (Mach Vortex)
Metaknight spins around, pulling people close to him into the tornado for a single, more powerful hit.
Like the previous one, you can rapidly tap B to increase the duration, but Metaknight's horizontal control is massively reduced during the move and if you use it in the air Metaknight doesn't seem to be able to rise as much, though using it grounded seems the same as the default.
The single hit does 9% damage and better vertical knockback than the default one, being able to kill Samus off the top of the screen at 150%.
Everything else about the move seems the same, other than the fact that it seems to have higher priority, able to beat out Homing Missiles and Super Missiles rather than just the former (though it's still not enough to beat a fully powered charge beam).
Neutral Special 3 (Heavy Mach Tornado)
This is a harder hitting version of the default Mach Tornado, but you lose the ability to gain any vertical height and tapping the button doesn't increase the duration.
The move will do 13-14% damage if all hits connect and the final hit has better knockback than the default Mach Tornado, it's sends them both a further distance and at a more diagonal angle, which is better in this game as vertical kills are much harder than horizontal ones for most characters.
This variation can kill Samus at around 130%, so it's not that much better as a kill move, but it is a bit better as an edgeguard setup, though the knockback is still a bit too vertical for that really.
The endlag on this move is also considerably larger, so you really have to make sure you're actually going to hit with it.
Everything else about the move seems the same, other than the priority which seems equivalent to Mach Vortex.
Side Special 1 (Drill Rush)
Metaknight spins forward, travelling halfway across battlefield. His flight trajectory is controlled via the stick, though the turning circle is quite high, so you'll never be able to go in the complete opposite direction.
The move is multihit, doing 1% damage a hit until the final hit which does 3% and increased diagonal knockback (though not really enough to make it a kill move, only killing Samus at around 170%), making for a total of around 11% damage, if all the connects hit - which seems to be much harder this time around unless you start angling Metaknight slightly diagonally after the first hit, otherwise he just seems to do 2 hits then go through them.
The move is useful for carrying someone off stage with you, but it still puts you into special fall so I wouldn't do it too far off the edge.
It has the same properties as the Mach Tornado, being able to beat out low priority moves and projectiles.
Side Special 2 (Speed Drill)
A faster variant that lacks the ability to control the trajectory, but the distance traveled is slightly larger and although the damage stays the same (1% a hit, 3% on the final hit), the knockback is greatly reduced, not able to kill Samus until around 275%.
Due to the fact that it's horizontal only, it's a bit harder to land all hits and get the 11% of damage, so I'm unsure as to what the advantage of this custom might be, it seems weaker other than the fact that he moves faster whilst using it, and that isn't particularly noteworthy.
Side Special 3 (Breaker Drill)
Metaknight's "shield breaker" variant, I say shield breaker in quotation marks because, due to what I believe is a pretty big flaw in the Smash 4 engine, this move won't actually be breaking any shields, not when used against anyone competent, atleast.
See, Smash 4 seems to have either 0 or very little shieldstun in this game, you can just drop your shield or roll pretty much any time you please and, because this is a multihit shield breaker, the person you used it on would need to stand still and hold the R button and not realise what the move was doing to get hit by it.
Nobody is going to stand there and have their shield broken rather than just roll away or drop their shield and eat the much more preferable damage and low knockback, so I highly question the point of this move
When not failing to break shields, the move has the exact same properties as the default Drill Rush, though it travels slightly less distance than it and the knockback is much lower as it can't kill Samus until 290%.
Up Special 1 (Shuttle Loop)
This move is probably the most changed from Brawl due to the removal of the glide mechanic, Metaknight does a rising loop-de-loop that consists of 2 hits that seem to always combo each other below reasonable percentages (they combo'd at 300%, not much point testing after that, at some point they stop comboing and the first hit kills though, as that happened at 999%).
The first hit does 9% and the second does 6% and decent vertical knockback, the startup is incredibly quick and the knockback can kill Samus off the top at ~135%, so it's a pretty powerful move, though without the glide you're now limited with your horizontal recovery as it is mostly vertical, use drill rush instead if you're too far away.
The move has no other extraordinary properties such as super armour, so I guess that's all there is too say about it.
Up Special 2 (Shuttle Flight)
The startup on the move has increased, but the angle you travel at is much more horizontal, meaning you can cover more distance with it.
Each hit does 1% less damage, leaving for a total of 13%, the knockback is more horizontal though, meaning you can kill at lower percents (killed Samus at 125%) and it can be used to carry someone off stage, though don't use it too close to the ledge, the move still puts you into special fall and there'll be no way of making it back.
Up Special 3 (Shuttle Dive)
For this custom, Metaknight sacrifices a guaranteed second hit for a more powerful second hit and increased vertical height.
He jumps much slower upwards this time around, then slowly dives and sharply turns back up to fly higher, it's very similar to the default except that it doesn't have the initial hit anymore, only the second one remains which now does 9% damage (though it degrades to ~4% if you hit them later on in the attack) and kills at the same percentage as the default..
Everything else about the move seems to be equivalent to the default, it's just a much better recovery option that's harder to KO with.
Down Special 1 (Dimensional Cape)
Metaknight disappears for a moment and reappears in the direction the stick is held. If you press B just before he reappears (or if you simply hold the shield or B button), Metaknight will perform a slash as he reappears that does 15-16% damage and does diagonal knockback that can kill around 135%
It will travel just over a quarter of the distance of Battlefield in whatever direction you hold, so it can be used to recover slightly like every one of Metaknight's specials, and it will put you into special fall, just like every one of his specials.
You're obviously invincible to projectiles and attacks whilst you've disappeared, as there's nothing there to hit, but the endlag is pretty high so you shouldn't really be using it as a dodge.
Down Special 2 (Dimensional Breaker)
I'm
pretty sure that this custom is supposed to be a shield breaker move, it does less damage (10%) in multiple hits, travels the same distance and has higher end lag, so based on this and the visual effects of the move, I'm just going to assume this move has shieldbreaker properties, but getting the CPU to just shield in this game is very hard, so maybe anyone else out there has some more info for me, it seems like that must be what it does because otherwise it has no upside whatsoever.
Down Special 3 (Dimensional Teleport)
This variation lets you control Metaknight practically uninhibited as he phases through the air, the travel distance is increased to halfway across Battlefield and the damage is increased to 17%, but now that Metaknight is a visible blur, you're no longer invincible to projectiles and attacks.
It's also impossible to cut the attack short and instantly slash, you have to wait the full one and a half seconds before the slash and you're vulnerable the whole time as you can't do anything other than move, so watch out for that as getting hit will interrupt the move.
There is also a small push back effect if you control the blur towards people, but it's only minor, everything else seem to be the same.
Final Thoughts
The shieldbreaker moves were very disappointing due to lack of shield stun in the game, I thought they'd be fun moves to use but everytime I hit someone who was shielded, they'd just roll out the way and take the damage instead, you have to really catch someone sleeping to break anyone's shield with that thing, maybe the Dimensional Breaker is better at it but I'm not convinced.
Otherwise the customs are pretty average, they don't really fill any extra roles Metaknight was unable to do before, it's mainly just "different type of recovery", "faster but less damage custom" etc. etc. not particularly interesting if you ask me.