Yesterday I've been introduced to Splendor (awesome game!), and there's one question stuck in my head. In one turn I've run out of options (no resources to collect, nothing to buy), so I reserved a card with a joker token. After some turns I bought it, and payed the full price (4 blue gems), and gave the joker token back.
Only afterwards did I realise that I didn't have to pay since I had the joker token - but does it work like this for a development card that requires only one colour?
Can I reserve a card that only requires one colour, nd then take it in the next turn by only giving the joker token?