Capricious Hellraiser is a six-mana 4/4 with flying
Incessant Onslaught has some pretty insane abilities to scale into a very heavy swing late game, making it a handy tech into certain decks
This unassuming rodent, printed in Return to Ravnica, basically required an immediate answer, or it would multiply out of control, each copy making the rat horde, and the rats themselves, grow bigger and bigger
We have the tools to take the aggressive role in many matchups, curving out with efficient creatures and backing them up with some tricks, but we can also be the control deck, generating card advantage with Wall of Omens, Thraben Inspector, and our blink effects before eventually running our opponent out of resources and winning the game
This is just an example of the kind of build that is possible and doesn't adhere to any kind of budget or limitation