Question about making keycap with figure inside clear resin

[envyy24]

Sorry for the title, I really dont know what is the exact term for that kind of keycap. It looks like this

Credit: Dwarf factory, see the album here - https://imgur.com/gallery/C7PK2z9

anyways I found this video which shows step by step process of making a key cap like that:

t=s

But there is one part that I do not get. After the person made the base and the fnar figure (12:40) then he/she proceeded to put the whole thing inside a big mold and fill it with clear resin(13:57). The big mold kind of appear from nowhere to me, or did I miss something here? Because i think that the customed keycap is higher than a normal keycap (due to having a miniature inside) therefore the mold for the entire keycap can not be made with a regular keycap. Or can it? I cant really figure this part out, please help!!

[suicidal_orange]

The technique is called encapsulation and looks like they're using an SA keycap mold.  SA caps are much taller than standard OEM or Cherry caps so plenty of room for fun stuff inside

[envyy24]

The technique is called encapsulation and looks like they're using an SA keycap mold.  SA caps are much taller than standard OEM or Cherry caps so plenty of room for fun stuff inside

Amazing, thank you very much!!!!
*off to buy SA keycap*

[Gastomo]

I still do many things. Well not good enough I want everyone's opinions.