Alone in the Dark, the first two levels. There's a lot of Kats in those levels; do the runs on elite with a partner, 2 at max would be good (a party of 2).

"Black kats are monsters that focus on powerful curse attacks. They can randomly be found in place of any spookat-type monster in any Tier 2 and Tier 3 level level of the Clockworks (Missions and Arcade Gates)."

So, the best places for finding black kats would be where lots of kats spawn, since black kats will take the place of a spookat when spawning.

The more kats = the higher the chance you will find a black kat

I recommend making a Tier 3 undead stratum; th ecurrent one has undercity levels, which is not a good idea for kat hunting. For now, I recommend the first two levels of the mission, Alone in the Dark. A black kat drops 3 pages, so far i got 6 pages from three attempts at Alone in the Dark. I prefer the undead stratum because variety is fun, and grinding is boring. Those missions get tiring, quick.

If we get some Scarlet Fortress levels, we will hit the jackpot on kats!!!

I can contribute my Dark Matter.

Forgot the name of it but, some gate had a candlestick keep at d19 it's the only level for that depth too

Alone in the dark has shock. I'd say weight of dakness is more friendly to run through.

^ yes please