Rank 10

To achieve Rank 10 you must first build the Intergalactic Cruiser Masterpiece. This is considered very difficult due to Transparent Brick and Nebular Crystal shortages.

Afterwards
Once you build the Intergalactic Cruiser you can go on to befriend Grok, the 5 Echo Prototypes, and Zenith.

Afterwards you can go onto getting the Dreaming Beam Infuser Module, and then tackle getting the ultimate game on MLN, the Rocket Game Module

The Highest Rank...for now...
Rank 10 is currently the highest rank (For now...). Don't worry, there might be more (although this has not been proven).