Creating a full, dazzling 2D platformer with original mechanics and visual effects is a significant undertaking that involves many steps, including designing levels, implementing complex physics, creating animations, adding sound, and much more.

We can start by setting up a basic foundation for a 2D platformer using HTML, CSS, and JavaScript. This initial setup will include a simple player character that can move horizontally and jump, with basic gravity. We can then build upon this foundation to add more features.

Here is the initial setup:

This provides a basic canvas with a blue square representing the player, a green ground line, and allows you to move the player left and right with arrow keys and jump with the up arrow. This is just the very beginning, and we can add levels, enemies, power-ups, and more complex mechanics and visuals in future steps.