Use for the Postcard, Flower Mask, Beast plushy and Beast Mask?

[Blinky]

Can't think of any way to use these items.

[Evayangelion]

I saw mailbox but dont know how to post my card to the ghost.And he disappeared when game end...

[TisTheSeason]

I'm not sure what the beast plushy or postcard do, but the beast mask barks when you press Z (Y with a controller) and the flower mask changes color when you press Z

[chirp_mp4]

No confirmed answer for the plushy, however the postcards actually have no use. I think there was a twitter post linked around in the community somewhere about it.

[squidmaster423]

they have no real use, the masks have special abilities, but they dont do anything important