Mario - Tips and Tricks

I'll add to this when I can.

-Iron

Jab: Comes out on frame 2, consists of three hits with the first two being capable of jab locks and pokes.

Forward tilt: Comes out on frame 5, a good get-off-me tool and can be angled.

Up tilt: Comes out on frame 5, decent juggling and combo option and can be used as an anti-air and kill move if the opponent is at ~200%. Very small horizontal hitbox but has enough vertical reach to hit past Battlefield's platforms.

Down tilt: Comes out on frame 5, very good (if difficult to time) 2-frame that can set up confirms into aerials until well into kill %. Decent range and can poke decently if well spaced despite its visible ending lag.

Dash attack: Comes out on frame 9, has a lingering hitbox, and is extremely easy to 2-frame with thanks to its high base knockback, but doesn't usually kill due to low knockback growth. Unsafe due to its long animation.

Forward smash: Comes out on frame 15 but has a surprisingly safe startup animation, making it deadly when coupled with the move's visible disjoint and massive KO power. Very good for 2-framing if angled; has a sourspot that still has powerful knockback.

Up smash: Comes out on frame 9 with a gigantic hitbox behind Mario, making it an incredibly useful out of shield option. Powerful knockback with full intangibility on Mario's head makes it a deadly anti-air as well; though it sometimes whiffs if the opponent is in front of Mario.

Down smash: The fastest smash attack in the game at frame 5, high KO power (which drastically increases if the opponent is behind Mario), and equivalent range to down tilt which means it can sometimes be used as an out of shield option. Doesn't reliably 2-frame due to its hitbox placement, but very good at covering ledge options/rolls and sends the opponent at a semi-spike angle. The two hits will infrequently connect with proper spacing.

Neutral air: Comes out on frame 3, an excellent combo breaker and can start and extend combos at many percents. Kills very well in an edgeguard situation if the clean hit connects (though it kills reliably from any stage position), and confirms into all smash attacks with the late hit.

Forward air: Comes out on frame 16 and consists of three hitboxes: the early hitbox hits with powerful horizontal knockback that kills well offstage, the clean hit is a deadly spike that comes out on frame 20 and can kill at ~200% onstage and confirm into itself near ledges (as well as other moves at certain percents), and the last hit is essentially a weaker version of the early hit that comes out on frame 24. Unsafe, but an extremely potent combo finisher and edgeguarding option.

Back air: Comes out on frame 6 with solid range and enough power to kill effectively at high percentages if the clean hitbox connects; the move overall is very effective for combos (particularly into itself for a psuedo-Wall of Pain) and pressure and arguably Mario's best move. A solid edgeguarding tactic, and the late hit is capable of confirming into down smash at kill %.

Up air: Comes out on frame 4 with a short hitbox duration, making it extremely effective for ladder combos, a very potent combo starter and extender, and capable of confirming into all aerials and up special at kill % depending on stage positioning. A solid juggling tool that can also kill at high percents.

Down air: Comes out on frame 5 with a massive, overlapping body hitbox that can effectively catch jumps. Consists of five loop hits that the opponent can infrequently fall out of (making the move an effective damage-racker) before transitioning to a conclusive, powerful blow that will always put any character into the reeling animation and is an immensely effective KO and juggling option that can still combo at lower percentages. Has a landing hit with fixed knockback, which perfectly positioned with certain loop hits can confirm into faster KO options at any % said moves happen to kill at.