One major problem with this set, as Mark Rosewater once explained, is that it is "parasitic." Meaning, its cards care very much about interacting only with other cards from the block, and Champions cards don't get along well with the game as a whole
Instead, rarity is represented by color
A Few Good Options There are a couple of cards that just seem good here being thematic and also highly synergistic
Of course, Jumbo Cactuar will have a big ol target on its spikey back as soon as it hits the battlefield, so its worth attaching indestructible or hexproof to it to prevent it from reaching an early grave
Brawl Legal Vintage Legal Timeless Legal Commander Legal Pauper Not Legal Oathbreaker Legal Penny Legal Toolbox Notes and Rules Information for Port Town: You may reveal any land card with either or both of the appropriate subtypes
"A Beginners Guide to Magic the Gathering"