Hide and seek is great fun! It actually stimulates an animal mentally and they consider it a game rather than anything to stress over.
A game I play is when one of my pups ask me for aomething. water, outside, a treat whatever. after they tell me, if I am in bed reading or on my phone, I throw the blanket over me and go to sleep. The reactions vary. One of them will jump on me and rip the covers off me and push me out of the bed, another will immediately lay down and curl up as if going to bed thinking its night night time. another will run back and forth and have a bit of a tantrum.