Here is the rough cost in coupons to get the event points to buy one of the items and the average cost for that same item over the last 4 months

Only the Great Tree event this week.

Item - cost - (average cost in recent events)

Items

Cave Key - 24 - (22)

Silk Clothing - 160 - (170)

Ninja

Nagato Edo - 120 - (100)

Kisame Sharkmode - 280 - (284)

Tobirama Edo - 360 - NEW