This is basically an area in which the community can share their additions to the platformer tutorials. If you have added anything to your game, you should consider posting it here so others can benefit from it.

Collectibles

Add various things like coins for the user to collect in your levels.

Power-Ups

Add special items that will enhance the player's attributes for a short time.

Doors

Use doors as an alternative to triggers in ending levels and changing areas.

Ladders

Place ladders that the player can climb.

Ledge Grabbing

Allow the player to grab ledges it is falling past and climb up them.

Moving Platforms

Create platforms that move around and carry the player with them.

Pathing

Implement a pathing system that can be used to direct the camera, enemies, or moving platforms.

Timers

Add timers to countdown certain events or keep track of the length spent on a certain task.

Checkpoints

Create checkpoints to spawn the player from when it dies instead of forcing them to start the level completely over.

Crouching

Allow the player to crouch and move around while crouching. This will also update the collision box, making the player shorter.

One-Way Collision

Add platforms that allow the player to jump through underneath but land on top.

Breakable Tiles

Place tiles that the player can break in a Mario-like fashion.