So recently there has been a lot of advertising; and to draw in more potential new and old players alike I propose some kind of coupon/code system. (Which many games utilise.)
There is 'monthly' promotions where players can claim 'Free' items; like when streamers are promoted by a game they say "Use 'INSERT CODE' here to claim XXXX gold coins and a unique 'Insert Special Thing". Code redemption could be found on the credits page.
Examples below:
-> Claim a free captain, just by logging on!
-> Get 1,000,000 gold coins upon signing up.
-> Get a 10% off any market purchase.