When I started here, all there was was bioactive ground. Other engineers said I was daft to build a base on bioactive ground, but I built it all the same, just to show 'em. It sank into the bioactive ground. So, I built a second one. That sank into the bioactive ground. So, I built a third one. That burned down, fell over, then sank into the bioactive ground, but the fourth one... stayed up! No, wait...