If you want to make slopes for real here is how:
Set a sprite to a 1x1 or 2x1, etc. image. Create it in an index loop, moving the new one down each time. Make the sprite of (new kind) slope (choose left or right).
Make an on kind player (or whatever kind the main character is) hits (slope left/right then inside that, write change mySprite y by -1 and change mySprite x by (if left, -1, if right, 1). (The code is in my pinball game)
Here is another example: