As mentioned earlier by Anton, game designer for SuperCity on Collection buildings, we’re going to have a mega building soon and here are some details:

From mega farm to mega flower kiosk,

• You can combine different buildings into one mega building.
• Free up space on the map and earn from different buildings at the same time!
• Mega buildings are available at the Department of Architecture.

 
Mega buildings in the game!
Select the mega building you want to build in the Department of Architecture.

Rules:

1. Gather several buildings into one and free up space on the map! Collect all necessary resources in the warehouse: standard objects and buildings of this type.
2. To build a mega building, send several common buildings to the warehouse.
3. Select a building on the map where a new mega building will appear.
4. Upgrade the mega buildings and you will be able to host more buildings!
5. After completion of construction, the Mega building generates profits like several ordinary buildings of this type.
6. You can only build one building of this type at a time.

 
That’s all I can tell you right now, but soon we’ll be back with more details! Stay tuned to this page for more news!