jace cards mtg beleren and put it into your hand All 15 Jace Planeswalker Cards

Spawn of Mayhem Spawn of Mayhem can be cast for as low as 3 mana with spectacle, and you get a 4/4 flying and trample creature

Until later, Abe Sargent

Thunderous Velocipede A vehicle that enables the perfect green ramp Gives creatures & vehicles 1/1 counters Crews 3, & has trample Thunderous Velocipede has basically everything you would want from a stompy vehicle green deck

There are codes in various real-life MTG products as well

I'd say that Kozilek is even TOO GOOD for most playgroups, as either he gets destroyed by artifact hate or he just takes over games

In a competitive format, you need to worry about both the tournament structure and the metagame