User blog:Solowing106/Tunnels

Please comment, which one is the most intense or which one is the hardest or easiest? Air Combat tunnel, Geothermal and Fortress Intolerance in AC2, Geofront in AC3, Megalith in AC04, Solo Island and Sudentor in AC5, Avalon in ACZ, Cobalt and Archelon in ACX, Ragno and Chandelier in AC6, or the Silo in ACX2?