Hi @tsnaks, last month I organized a contest that developed in 10 different challenges, one per day (so 10 posts). The challenges were not the same: they range from being active on steemit, supporting other members, random draws, etc ... (You can find them on my profile)
In each challenge there were 3 winners, who received extra lottery tickets.
On the eleventh day I made a draw and the lucky winners received 17 steem or 3 steem Monsters packages (the prize were chosen by the winner) You can do the same with the single cards. It was a success more than 56 people participated.