Enchant creature
Enchanted creature gets +1/+1 and has “Whenever this creature deals combat damage to a player, you may draw a card.”
At the beginning of your end step, if you didn’t attack with a creature this turn, sacrifice Curious Obsession.
Curious Obsession's last ability is satisfied if any creature has attacked, similar to raid abilities. The creature it enchants doesn't have to have attacked.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.