Campaign Concept and Testmap

I made a small map to showcase some techniques on how to make singleplayer maps.
This map contains 3 stages with increasing difficulty and different objectives.

Download map_campaigntest.pk3

Stage 1:
Get past 4 zombies, call an elevator and collect the required key to open the door.

Stage 2:
Collect 2 keys being surrounded by monsters and solve a small jump-n-run section.

Stage 3:
Get as fast as possible to the goal while turrets aim at you.

Along the way you unlock different weapons and armor. The spawnpoint moves and creates a persistent checkpoint.

Feel free to expand upon it. Maybe you also have some ideas that could be included in a campaign.

Licenses are CC0 and/or MIT.