quarantine 'em

The epact of any given year is the "age of the moon [i.e. day of the lunar month] on 1 January". But sometimes it's 30 when it should be 29

The epact goes up by 11 every year, mod 30. But not always! It also doesn't tell you WHICH lunar month it is

Basically the epact is a highly complex derived property from a relatively simpler underlying lunar calendar

And understanding epacts just makes the underlying structure of the Metonic cycle seem unapproachable

Now here's the thing. I'm not a historian, so this is second-hand, but from what I understand this IS deliberate obfuscation by the Church

Making Easter difficult to compute makes you reliant on the Church's calculations to know when your feast days should be celebrated

And once you can convert any Gregorian date to/from a lunar date (i.e. a position in that cycle) (also very doable), Computus becomes simple