Construction Yard --> Tesla Reactor and Barracks
Construction Yard + Barracks --> Sentry Gun and Wall
Construction Yard + Tesla Reactor --> Oil Refinery
Construction Yard + Oil Refinery --> War Factory and Navalyard
Construction Yard + War Factory --> Radar and Service Depot
Construction Yard + Radar --> Battle Lab and Flak Cannon
Construction Yard + Battle Lab --> Iron Curtain, Nuclear Missile Silo, Cloning Vats, Tesla Coil and Psychic Sensor
Construction Yard + Cloning Vats --> Oil Supply Facility
Barracks --> Conscript, Attack Dog, Engineer and Shock Trooper
Barracks + Radar --> Crazy Ivan, Flak Trooper and Terrorist (for Cuba only)
Barracks + Battle Lab --> Spy and Desolator or Yuri
Barracks + Battle Lab + Allied Stolen Tech --> Chrono Ivan
Barracks + Battle Lab + Soviet Stolen Tech --> Yuri Prime
Warfactory --> Terror Drone or Grinder (replaces Terror Drone for Cuba), Flak Track, Rhino Tank and MCV
Warfactory + Radar --> Twinblade and Tesla Tank or Demolotion Truck or Heavy Tank (Cuba doesn't have it)
Warfactory + Battle Lab --> V3 Launcher, Apocalypse and Kirov
Navalyard --> Giant Squid, Attack Sub and Ampfibious Transport
Navalyard + Radar --> Sea Scorpion
Navalyard + Battle Lab --> Drednaught
NOTE= This Tech Tree always gets updated when a new version of RA2 New Age for War uploads...
And also RA2 New Age for War REMASTERED 1.2 always reuploaded over and over again...