Dessire
Regent
best DS, world fair upgrade kit. have a 2nd one at lvl 10 not only increase blue galaxy FP average but you can delete 3 black doorway + 1 SoK. or 1 royal ship + 1 black doorway + 1 SoK. for a player like me, who wants to produce 1000 FP one day (im at 927 per day) this building is a must to have. 9 checkmate squares are just waste of space. (more FP more GB levels per day <3 )