Half-Life homage Vertigo 2 coming to PSVR 2One advantage of the solo effort is that Tsiakalis-Brown was able to pursue his creative vision in a linear story mode filled with bizarre aliens. The Half-Life series served as his main inspiration. Half-Life homage Vertigo 2 coming to PSVR 2One advantage of the solo effort is that Tsiakalis-Brown was able to pursue his creative vision in a linear story mode filled with bizarre aliens