Now, i know this data isn't really that beneficial, but i was bored and decided to find out anyway.

I came up with this equation

C=A(T/R)+xP;

where: C=total brittle candy
A=average brittle candy per run
T=Time spent grinding (in minutes)
R=Total time taken to complete each run(including loading time)(in minutes)
x=Amount of PK (prestige) missions
P=Average amount of BRITTLE candy per PK run.
(Don't ask... I just like formulae)

I assume:

• You want the scarab mask (duh), so 75 total brittle candy
• An average of about 2 Brittle candy per run
• A time of 7 minutes per run
• 2 PK missions
• an average of about 6.5 Brittle candy per PK mission

When we substitute the value in we get:

75=2 (T / 7) + 2(6.5)

Now after some algebra, we get a result of T=217 minutes, or 3.617 hours.

TL; DR It will take about 3 hours, 40min of straight, efficient grinding to get a scarab mask.

Thats a lot better than the Katastophe, huh?

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Note: My averages are just rough estimates based on my experience, I haven't been writing down the results of my grinding. Feel free to correct me.

By the way, my equation was organised like that because i originally had one without the PK stuff used to predict the amount of brittle candy per hour = about 17.