Kratos, Stoic Father is a mythic Legendary Creature — God Warrior card from Secret Lair Drop (SLD), collector number 2213. Current market price: $8.65 (foil $11.05), TCGplayer market prices via Scryfall.
Whenever you attack with one or more Gods and whenever a God dies, you get an experience counter. At the beginning of your end step, put a number of +1/+1 counters on target creature equal to the number of experience counters you have. Partner—Father & son (You can have two commanders if both have this ability.)