Stone beat to the scissors, .. scissors beat to paper, ..paper win to rock.
No. Just like in English, scissors is a plural noun meaning a pair of scissors.
Gleb, No, you can't substitute "shoe" just because you know a similar game! Duo did not give you zapata, and el bujo es jefe aquí. ;>)
"Stone" is made from "rock". I think better translation is: "piedra" = stone; "roca" = rock.
It's a rather small rock in the game, about the size of a fist, so piedra fits better here. Roca is usually larger, about the size of a person and above.
Don't we say, "Rock, scissors, paper" in English? Duolingo wouldn't accept this answer.