Imho GHEIST is kinda hard... mono Rescue and Uppers+Montana are prolly the easiest since they let newbies learn about low pill (1-2 pills, which means Vortex is kinda good as well as a half deck with Montana/Uppers) bluffing before going for harder meta that Bangers, ulu, GHEIST, and the other clans are in (3-4 pills, variations of 5-7 pilling as well).
Pirana takes a lot of bluffing and prediction. I wouldn't not recommend them, since a lot of their decent cards are quite cheap, but I wouldn't call them the best for beginners. It's your call, though.
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