What if there was some weekly event where if you reach the Core,a Knight that wasn't here before was now here.He says something like,"Young Knight!An evil threat has attacked the Core!Pleases help us,or Cradle will fall apart!".The only option is to click:'Yes sir!On my way!'.If you go to the edge looking at the Core,the icon for lifting up minerals appear.If you press attack,you will delve inside of the Core by falling.Then it does the sequence for going deeper in the Clockworks,and the level is called 'Core',and the Depth is 30.It has every enemy except like Impostocubes and Love Puppies.Attacks are greatly powered up and enemies will have a little more health.
When you beat the level,you go down the lift.The name of the level is ???(=P),and its Depth ?.There are Heart generators,therefore refering there is a boss.A party button is in a square room.When all party members step on it,the music stops and a Dialogue Box appears (like Vanaduke),saying:"Fools...you are in my path...and as Supreme Ruler of Cradle,I shall destroy you!".Then diffrent music plays,and a shadowy figure appears.Its a dark shadowy blob with hands that aren't attached but can be controlled.
Might as well just wait a bit before I tell you battle tactics.If you feel like it,give some ideas.
I'm pretty sure OOO has an idea for the bosses they're going to develope.