This is something that I think could help a lot of players. Mcleodgaming should add a little tip box before a match (Exactly like in smash 4) so we could learn something we may have not known before. There should also be an option in the vault that should let you choose which tips you want to see. Feel free to discuss any tips if you have any.

Ex : Use Kirby's Hammer (Side Special) to catch rolls.

I have one
"Flowmotion is not a good combo starter"

I'll do one for all of my mains

Fighters - Kirby
When you swallow with Inhale, its low knockback can lead to combos. And you get a Copy Ability, too. Neat!

Item- Assist Trophy
The devs know about that bug, no need to report it.

Stages - Dream Land
That mighty tree with a face in the background is called Whispy Woods.
He doesn't like fighters in his lawn, so he will blow away anyone using wind.

Item - Pokemon: Magikarp
"Forget it, nothing happened"

Fighter - Pikachu
If you use Quick Attack into the ground, you can jump immediately. This is called Quick Attack Cancelling. It's perfect for positioning, combos, or even using Quick Attack again!

Or this for Pika:
His down-aerial is ridiculously powerful. Good luck surviving it if you get it!

Fighters - Jigglypuff
Using an uncharged Rollout in the air followed by a Rest will instantly wake Jigglypuff up when she hits the ground. I guess she wanted just a cat nap.

Stages - Gangplank Galleon
Ships in the background will shoot cannonballs onto the galleon. Once there, you can launch the cannonball into other fighters. Talk about having a ball!

Stages - Sky Sanctuary Zone
Once a gigantic temple in the sky, now a place full of ruins and growing vegetables.
It has gotten so old the bridges are very fragile, so they fall in pieces if anyone lands over them.

Stages - Saturn Valley
A peaceful village inhabited by the Mr. Saturns. There's a hot spring at the center which will heal anyone who enters it.
Let's just hope Master Belch stays out of there, though...

Stages - Phase 8
As the volcanic stage this is, it's no wonder why it's choke full of lava, it may come from the ground or fall from the ceiling. Be careful!

Fighters - ichigo
he can make more things than the side b and dash

Stages - Crateria

There will be a warning sign which will warn you about a certain hazard. Stay in the glass "area" to stay safe.

Stages - Mirror Chamber

These mirrors can teleport you from one mirror to another. Want to approach a defensive opponent? Just hop in and surprise your opponent.

Black Mage-

Up, Side, Down Smashes: If you fully charge any of his smashes, it becomes a completely different attack. Try it out for yourself!

Naruto -

Nobody loves you and you will die alone. Believe it!

Sora-

Wait for Beta because you'll never git gud with Sora in 0.9b.

Play something else.