Pheromone Concrete seems a bit overpowered from the description...

- Decelerate Concrete changed to Pheromone Concrete. Enemy units can't cross. Idea from Darkfrei

Doesn't that make it basically invincible walls, which is significantly overpowered?

Yeah, but it uses Alien Artifacts to create and once mined, you lose it.
So it is very powerful, but also an Artifact sinc.

On a death world right now I'm sitting on almost 3000 stacks of full artifacts, sooo... Way overpowered.... ^.^;

The slowdown concrete was super useful for car parking though, now my cars speed up into the surrounding walls with this... >.>

Okay, I added an update. Now Pheromone Concrete will stop working about an hour after placed.

Hmm, is that going to be an ontick event? Does it get more costly with a lot of them or does it stay below 0.01ms at most?

I really like that idea for it though! Great quick defense while setting up something more permanent. Any chance at making the time configureable in the settings (I'm thinking of something more like 5-15 minutes on my deathworld server, hmm, tiers of it would be interesting too...)?