Can anyone think of obstacles for a 2D platformer where the player can slow down time

I'm currently working on a platformer for Uni where you have three time-based powers, stopping, slowing down and speeding up time, but i can't think of obstacles for the slow time mechanic outside of some fast doors

- Something that is immune to the slowing of time (moves at normal speed regardless)

- Something that gets more powerful while time is slowed (limits how long you can slow time)

- Something that cancels the slowing of time when you collide with it

- Something that now damages the player when time is slowed (limits when you can slow time)

Ways to nerf time slow:

Limit the duration of time slow.

Limit the number of times you can use time slow.

Add a penalty after using the time slow.

Add a beneficial mechanic that can't be used during time slow.

Ways to make time slow useful:

Areas that are otherwise impossible/difficult without time slow by

a. Volume of information eg. bullet hell.

b. Size of hazard such as an explosion or beam such that you can't dodge in time normally.

c. Number of enemies to dispatch without getting overwhelmed.

State change of normally moving objeccts/hazards such as bullets turning into platforms.

Any reflex/skill based puzzle.

You need to come up with a goal for the game.

What are the win conditions, how does the player win and lose?

The way you design obstacles/challenges for a game all depend on what the player is aiming to do.