The "Joker Symbol" only transform from "Golden Symbol" of elimination.
The “Joker Card” comes in two modes: “Big Joker Card” and “Little Joker Card”.
Landing the "Big Joker Symbol", it will replace 1 to 4 number of symbols (Except the Scatter and Joker Symbol) randomly pick on reel 2 to 5 by "Big Joker Symbol".
Landing the "Little Joker Symbol", The "Golden Symbol" transform to "Joker Symbol" only.
"Joker Symbol" substitutes for all symbols except Scatter.