This BETA version of CIU only has CI4 and CI5’s waves. Where are CI2 and CI3’s waves in CIU? That is a hard question. I think CIU should have many waves from CI2 and CI3. Example:
- Boss Battle.
- Bonus Challenge wave.
- Double Trouble and Treble Trouble (CI3)
- Classic Invasion (CI3)
And those waves can collect key as same as CI4 and CI5’s waves.