If you've tried to get on the Mario Tennis Aces court in the last couple of days, chances are you'll have run into two aggravating folk: the swashbuckling shit-eating grin of Waluigi, Nintendo's favourite mischief maker; and the robotic "I can hit any ball on the court" arms of Bowser Jr.
Nintendo of America's Reggie Fils-Aime mentioned during E3 that the publisher would be doing some competitive experiments with Mario Tennis Aces, and as a result, the balance of the game's meta has some importance. And as it stands, two characters carving up the leaderboards.
It's no coincidence that they're both Bowser Jr. and Waluigi, the defensive characters that have the best reach and court coverage. Reach allows your character to charge up a little bit faster, since you'll be able to reach the ball without losing form. It's best seen in this clip, where Twitch streamer c_m0 gets maximum charge on a shot with Bowser Jr — who starts charging on the wrong side of the court:
The court coverage has another advantage, too. Stars appear on your side of the court whenever an opponent returns a ball that doesn't have the same amount of charge, but a star doesn't appear if the ball is returned correctly with a trick shot. Properly timed trick shots are also the fastest way to build energy, and the more energy you have, the more you can spend for zone shots, returns, or just for positioning to bully your opponent around.
This, mind you, is the case for all characters. Anyone can charge up a shot to maximum. But the reason why it works for Waluigi, and Bowser Jr in particular, is that they have a great drop shot, a good charge shot and the level of reach that matches the Bowsers, Chain Chomps and Donkey Kong.
Bowser Jr also has a fraction better accuracy than Waluigi, making its shots go a little further towards the edges of the court. But since their drop shots are so versatile, and they don't have the disadvantages that smaller-bodied characters like Rosalina, Boo or Yoshi do, it gives them the biggest capacity to respond Mario Tennis Aces's most dominant strategy: trick shot abuse.
(As of this morning, 23 of the world's top 30 players mained Bowser Jr. and Waluigi. The Australian rankings aren't much different: 21 out of the top 30 players preferred the defensive characters.)
Two keys with trick shots, as outlined by YouTuber Quizzle below, is that you can buffer trick shots before the enemy hits the ball. The most common time to do this is immediately after your serve: unless the opponent charges up a deep lob, your character will skip forward and immediately do a drop shot.
(Small hint: the types of shots characters hit from a trick shot are fixed, depending on the direction of the input. Launching forward will always be a drop shot, backwards will always be a flat, while sideways will always result in a curve, or an especially bendy one if you're Rosalina / King Boo.)
Now while you don't get any extra energy from this — if anything, you'll lose a little for a slightly mistimed shot — it does offer an immense positional advantage. Firstly, players can control the direction of their trick shots, so a drop shot that's diagonally away from your opponent makes it harder to instantly respond with a trick shot of their own, and if their reactions are off, they might even lose form trying to return the ball. That means you'll be able to charge up any shot in response: you could lob to the opposite diagonal corner of the court, double tap a strong volley to encourage them to burn energy, or just charge up a shot for extra metre.
Secondly, taking control of the net - or at least halfway towards the net - gives you full control of the court. Attempted lobs will either grant you a star, which you can run towards or use zone speed to get in range of, or you can simply trick shot backwards for a huge gain in energy. (Remembering to cancel a charge with L also helps here.) All drop shots will immediately be within your reach just by charging, so there's no threat there either.
A clip of a Mario and Luigi character getting full charge shortly after the point begins
Because the more powerful, slower characters have a harder time moving around, you can effectively bully them with cross-court shots and a mix of drop shots/diagonal lobs/hard volleys. Eventually, the Bowsers/Spikes/Donkey Kongs of the world will have to burn energy just to get into position. And since Waluigi and Bowser Jr. have comparable range — as well as a great angle on their drop shot, for Bowser Jr, and a powerful volley game for Waluigi — you can just bully them from side to side until the ball is eventually out of their reach.
Fortunately, you don't actually have to play Bowser Jr. or Waluigi if you have enough patience. Mario Tennis Aces lets players cancel out of any match before it starts, without penalty, so you can continually dodge the matchup in favour of another one. (It's a system that's designed to stop players from having to play people with incredibly laggy connections.) This goes for the semi-finals and championship finals as well, and some players on forums and social media have started switching characters just so they don't get dodged repeatedly.
The answer to all of this, eventually, will be a nerf. Apart from the timing of trick shots being too lenient when going forward or backwards, it would also help if the amount of metre gained was minimised a little. Even just a narrower angle on the trick shot would encourage people to spam it a little less, resulting in more star shots coming into play (which would be an indirect buff to the powerful characters).
Another change that could help is knockback on serves: it's a common technique to walk well inside the baseline for a return, since the knockback is fairly minimal (especially on Waluigi/Bowser Jr.). If players were punished a little more on a standard serve, the server would be able to charge up more on the follow-up shot, which at least evens out the metre gain in the early stages of the point.
Either way, the best strategy right now is to mix it up as much as possible. Alternatively, you can just dodge Bowser Jr. and Waluigi into perpetuity, although given how poor Waluigi has been treated by Nintendo already, maybe just leave it to dodging Bowser Jr. At least Waluigi's drop shot isn't as good.