You must have thought that kanna kishin is fking dead. Then, you are wrong. It is actually still alive.
Buying ringer kanna don't work very well.
But if you can buy ringer kanna + 2 kanna to kishin you will get back the old spawn rate!
MapleSEA following JMS.
1 kishin can stack with 2 another kishins. Maximum you can stack up to 3 kanna kishin.
This means 3 kannas kishin together in a map you can get back the old spawn rate! Old spawn rate is the one that provide massive amount of spawns!
Now, it is burning time! Train 3 kannas for your use next time!
Credits to Ken in game, which I saw he was using 3 kannas and asked him questions. =)