To Radzio45: it's not an error, it's because of rounding. The purple circle increases 1/1500 Laps/sec each level, which means 0.006666...Laps/sec, rounded to 0.007 as you see. So 13/1500=0.087, no problem.
The main advantage of rebirth is the level system, and all the RP can only upgrade something that increases level progression speed. Now you badly nerfed the level system that makes level completely worthless, and so does the rebirth. I won't rebirth anymore since sacrificing all my progress for 5x -> 5.5x speed is totally not worth it for me.
Just started to play this game
"Hmm..This is so monotonous, maybe only for 5 minutes of playing"
*2 hours later*
"Hey I just reached 1 quintillion, let's watch these beautiful circles spinning for 5 last minutes and go to bed."
*1337 hours later*
"Just...5...more...minutes..."
1.I think the health bar is way too long in Endless Mode.
2.I encountered bat king at 15 sec in Endless Mode(lv46). Is it a bug?
3.There should be a button to access to bestiary and medals in world map.
 "Revolution Idle 2"){kind=icon}
 "Tap Tap Infinity"){kind=icon}
 "Sentry Knight"){kind=icon}
 "Idle Mine"){kind=icon}
 "The Peacekeeper"){kind=icon}
 "Super Can Knockdown"){kind=icon}
 "Billy the Pilot"){kind=icon}
 "Burrito Bison Revenge"){kind=icon}
Just fixed! Thanks for reporting.