Tips about a character's background and how to use that character can appear at random intervals on the loading screen. The player can also access the full list of tips at any time in the "Vault" section. The following tips are copied verbatim from the in-game text.
Marth's Origins: Marth debuted in the first Fire Emblem game in 1990, but that game wasn't released in North America until the Nintendo DS remake in 2009.
In His Series: Marth is the protagonist of the first Fire Emblem series game, Fire Emblem: Shadow Dragon and the Blade of Light. He's the prince of Atlea and was driven from his homeland.
Shield Breaker (Neutral Special): This move leaves you wide open, but if you charge it to maximum, it can break an enemy's shield in a single hit.
Midair Shield Breaker (Neutral Special): Marth will move forward slightly if the move is used in midair, so it can be used to recover when trying to get back to the stage. He'll move farther when the move is fully charged.
Shield Breaker Techniques (Neutral Special): By entering up or down the moment the move starts, you can change the direction the blade strikes. You can do just a little bit more damage by hitting an opponent's head.
Dancing Blade Combo (Side Special): Keep pressing the button to turn this into a four-hit combo. Holding different directions will change the angle of the strike!
Dancing Blade's Color (Side Special): Marth's sword leaves a trail as he swings it, and the color reflects the attack's height. Blue is high, red is middle, and green is low.
Dancing Blade's Sideways Swing (Side Special): Hold toward the foe you're attacking on the fourth swing for an attack that launches foes much farther than the up or down versions.
Dancing Blade Up (Side Special): Press up on the fourth swing for a slice that will launch your foes. This swing is excellent for netting some KOs!
Dancing Blade Down (Side Special): During Marth's Dancing Blade combo, tilt the control stick down on the fourth swing to finish the combo with a powerful series of blows to your opponent's feet!
Aerial Dancing Blade (Side Special): Use Dancing Blade midjump to make Marth rise slightly in the air. Even during short hops, you'll be able to use the attack multiple times with this method.
Dolphin Slash (Up Special): Just before the attack comes out, Marth will be invincible, but it works a little faster in the air than when on land. Once you get used to using it, you can even use it to break up an opponent's combo.
Counter (Down Special): The counter depends on the attack it is countering. A countered smash attack may KO an opponent!
Critical Hit (Final Smash): In this Final Smash, Marth rushes forth with blazing speed. If you go too far, you can press the button again to stop on the spot.
Dragon Killer (Side Smash): The tip of the blade has astounding launching power. It's a bit hard to aim for a hit with it, but that just means the rush you get from landing a clean hit feels even better.
About Face (Back Air): This is a unique move in that Marth can change his direction while attacking. After the beginning part of the move, he'll change direction in midair.
Sword Characteristics: For moves that use Marth's sword, the base is weak and the tip is strong. Try to maintain a good distance when fighting so you hit your opponents with the tip.
The Three Fastest Walkers: Marth and Lucina are tied for #1, with Fox at #3. Walking doesn't leave you as open as running; patience can be a virtue in battle!