Finally, pack some win conditions that leverage your tribal strengths , like massive lifedrain effects or sacrifice loops that end the game on the spot
Here is a list of the cards I have noticed: Lighthouse Chronologist, Artificer Class, Barbarian Class, Cleric Class, Druid Class, Fighter Class, Monk Class, Paladin Class, Ranger Class, Rogue Class, Sorcerer Class, Warlock Class, Wizard Class Phyrexian Dragon Engine Meld seems to have a similar issue
Frustratingly, since all the backgrounds are monocolored, you won't be able to play all these cards in the same deck, unless we get that rules change for hybrid mana
Brave-Kin Duo Another 2-for-1 for pet-ability, Brave-Kin Duo is the little 1-drop that could
Loxi: Really cool way to ramp and/or enable landfall triggers
If you want to acquire additional cards and get some cool accessories, consider purchasing an Illumineer's Trove