In the past, the next dungeon always shows up not long after we obtained the ofudas. If we get it here now, we could be very close to getting that door open.

[ They're right here in the boss' room. There's a good number of them. ]

Keeping the ofuda means the Kotengu won't get stronger either... And we can prevent the town from getting destroyed too. We'll have to kill the Daitengu if we want to protect the town.