Shingen is coming out in a couple of weeks and will cost 600 HSP.

T1 and T2 Alchemist, 300P.
T3 Alchemist, 600P.
T1 and T2 Samurai, 600P.
T3 Samurai, 600P.

2100P / 300P/event = 7 events = 7 deadly sins. One full round gets you all of them.