Avicii is a Goomba that first appeared in Hotel Mario. They have the same look as Goombas, only with 2 thicker black eyebrows and longer tusks.
History
Hotel Mario
Avicii first appeared in Hotel Mario, where they were found in Ludwig's Thump Castle Hotel.
Super Mario Bros. Ultra
Aviciis also appear in Super Mario Bros. Ultra, where they were found in the Ice World.