Your own planet. When upgraded to at least level 1, unlocks several new features.
To upgrade your planet you must build and then sacrifice a single creation:
|Level 1||Earthlike Planet|
|Level 3||Solar System|
You can increase your planet's level past 5 by completing Ultimate Universe Challenges. The maximum planet level is 50.
With the exception of the Ultimate Arty and Clone Buildup Challenges the upgrade level and unlock status of the Planet persists between Rebirths and Challenges.
Planet Multiplier Edit
The planet multiplier is the product of your powersurge, UB, and UBv2 multipliers. All 4 god stats are increased by this multiplier, making it a large source of power in the late game.
Formula to calculate PowerSurge+ needed to bb PowerSurge:
12,000,000,000 / (Planet_Level+1) / Clone_Amount * 100 = PowerSurge+ + 100
I.e. 5M clones, planet level 65 would look like:
12,000,000,000 / 66 / 5,000,000 *100 > 3636 = 3536 + 100 = 3537 PS+ levels needed to bb PS with 5M clones.