Byleth's neutral game consists of applying safe pressure on your opponent, and punishing their response to the safe pressure.
In neutral, the best aerials Byleth has are fair, bair, and nair. Fair and bair serve a similar purpose, applying pressure from a distance. Nair is used to shieldpoke, as well as is one of our best punish tools in neutral, as it lingers a long time, even enough to catch spotdodges, and also has very strong follow ups, which we will cover later. Landing nair, also known as nairquake (abbreviated NQ), is -9 on shield, meaning it is not very safe when used directly on shield if it doesn’t shieldpoke.
For fair in neutral, there are a few movement options to keep in mind:
IDJ Fair - Performing an IDJ fair allows you to fair in the air, then land with another fair, a nair, or a bair. This is very effective at controlling aerial space.
FH Fair - FH fair leaves enough time to land with a nair, to fastfall and use a tilt, or to do a DJ fair. If you choose to do a DJ fair, then you can land with another aerial just like with IDJ fair.
SH FF Fair - This is the fastest way to safely get out a fair at ground level in neutral. While it puts little pressure on an aerial approach, it controls the space in front of you, making it hard for the opponent to perform a grounded approach.
Platform drop FF Fair - If you do a platform drop fair with a buffered fastfall, you will land with a fair one frame before hitting the ground (when on battlefield), making this very useful for punishing someone overextending when you’re on a platform.
IDJ and FH fair are especially good because it conditions opponents to stay grounded, which allows us to pressure with our tilts. SH FF Fair and Platform drop FF fair are also very strong, but more situational. Keep in mind that if you use only one of these things, you’ll get very predictable. Make sure to mix it up.
Due to Bair’s higher endlag, we cannot use idj bair in neutral, and FH Bair is only able to be followed up by landing and using a tilt, instead of using an aerial. Due to bair’s one frame slower startup then fair, you also cannot do a platform drop buffered fastfall bair on battlefield, and must instead time it manually. Due to these things, fair is often easier and overall better in neutral, but due to bair’s strength and ability to set up for an edgeguard extremely well, bair still does have some use in neutral. Most often, you will want to SH FF bair if using it in neutral, unless calling out a jump, in which case you want to FH bair.
Byleth’s tilts are fairly simple to use in neutral. Utilt works as a simple yet effective anti air, and at low % can combo into nair, at mid % into uair. Ftilt and Dtilt are simple grounded pokes, used to catch approaches and pressure shields from a distance. Dtilt hits lower and further then ftilt, and also shieldpokes. It is also a good combo starter, and also kill confirms into uair at higher %s.
Another large part of neutral is Byleth's neutral special, Failnaught (FN). FN is a strong projectile with two different shots, a somewhat slow but strong arrow which we call FN1, and a slower but stronger laser beam we call FN2.
FN has the ability to cancel up until frame 60, meaning unless you charge beyond that point, you have a very low commitment on actually shooting. What makes this so good, is that FN1 releases on frame 45, meaning your opponent will never know if you'll shoot FN1 or begin charging FN2 then cancel the shot, unless you get predictable. This is known as Failnaught Cancelling (FNC)
Because they never know if you'll shoot them or not, they have to deal with the arrow. If they act too soon, however, you can easily cancel the shot and punish them for the option they chose. And if they stop dodging the arrow because you cancel it, you can just shoot them with it. This creates an excellent bait-and-punish situation that byleth heavily benefits from.