To those thinking the chances of a rare card are 1/6: No.
This is how these types of games get you.
The 6-card layout is nothing but a mind-game, just like Valve's CS:GO gun slot. Your chances for rare or higher cards are a static percentage, usually around 30%. What you get on this percentage scale is applied to whatever card you click on, on-the-spot. It's random number generation that only LOOKS like a 6-card monte.
Not matter what card you click on, you have the same exact chances of getting a rare or higher card, because the cards are generated AFTER you make your decision, not before.
FOR EXAMPLE: Say the game shows you 6 face-down cards, and you have a chance to draw an SSR card. Your chances of drawing that SSR card is NOT 1-in-6. It's about 0.05%. The 1-in-6 is a trick, and what you get will be decided on an RGN after you click, which will very likely fall outside of the SSR hit range. But the game will reveal one of the other cards as the SSR card an make you think you were 'so close'. You weren't.
This is how all gacha mechanics work in F2P games.