Age of Wonders: Planetfall

U can unlock 3 achievement by doing this (Es Teq reformer, Es Teq Prophet and A new Beginning), simply unlock the skill in the science tree and start the doomsday weapon in the same way of the previous doomsday achievements, when only 1 turn left to launch the doomsday weapon save the game.

The next day the weapon will be launched and a message with 2 options pop up

Choose the option u want and 2 achievement will unlock, then reload and choose the other one to get the third one