What does [Verb Pre-Masu Form] + [shi] do in this context?


I am reading Cardcaptor Sakura in order to practice my comprehension. I see a
lot of pre-masu form verbs followed by し, and I am not sure if they are the
"giving reasons" し, the "connecting ideas" し, or something else entirely.

Here are some example sentences that I have had trouble with:

> カードに宿{やど}り **し** 魔{ま}力{りょく}をこの鍵{かぎ}に移{うつ}し我{われ}に力{ちから}を！  
>  (in this sentence, I want to know what the し in 宿{やど}りし does)
>
> 「クロウ」の創{つく}り **し** カードよ  
>  (in this sentence I want to know what the し in 創{つく}りし does)

Thank you very much for your help

