How do I make a keycard vault like area

[Blizzard]

So in my game their is a place where you get upgrades and the upgrades give you green keycard and 1 of them aka a super upgrade gives you a gold keycard how do I make a area that requires a number of keycard to unlock?

[Godatbedwars]

use vending machines and checkers I will explain later I gtg

[Apollo]

You can use a hidden vending machine as the easiest option. The vending machine should wire to a barrier and the barrier should block the area.

[The_Pro_Of_Pixels]

Use the vault thingy but use invisible vending machines to open it so when they but it the prop hides