Jamaharoa! I wonder if it's another dimension when so strong power gathers... I remember! Hi-ness said that "the hole" which leads to the Ikuwkan is opened! The time and the dimension are exceeded, and it is dangerous because it is possible to run to another world.
I think it's pretty safe to say that some DLC for Kirby Star Allies is being teased here. I guess we'll get the full reveal in a matter of days!