To make Serial happy, a mere dish scraping ustensil is enough. He goes into a trance at the mere sight of this accessory.
And, if by any chance, one decides to take him back his fetish toy, he will not hesitate to grumble for defending his spoils !
Another little habit, to throw his toys directly into his water bowl, just for the pleasure to take them out of it and to throw water everywhere. The wet soil, this is very funny, it is just like an ice rink :-)
Once he reached his daily quota of silly things, he rushes to call for cuddles and give some, with big friendly head-butts and profuse resounding purrs !