Duke, Goodest Doggo

Playtime - You may exert Duke, Goodest Doggo
as it attacks. When you do untap target creature
you control. (An exerted creature won't untap
during your next untap step.)
Whine - at the beginning of your endstep if
Duke, Goodest Doggo is untapped, tap all other
creatures you control.
Partner
"Duke's sad whine of boredom always reminded Max
to take a moment and engage with his life"