Most active at liminal thin veil times

Cat Sìth

The Cat Sidhe is said to be particularly active during Samhain, when the veil between worlds is at its thinnest.

Wanyūdō

The creature is particularly active during the Obon festival, when the boundary between the world of the living and the dead is at its thinnest.

Ceffyl Dŵr

It is said to be most active during twilight hours or on misty days when the boundaries between the physical and spiritual realms are at their thinnest.