The scalability makes for a unique strategy that'd probably involve recursion and/or graveyard shenanigans, something the Spirit type (all Zuberas are also Spirits) already has going for it
8: Search your library for an artifact or creature card, put it onto the battlefield, then shuffle your library
Unfortunately, you also need 4 of these for Legacy, as it has a unique effect and generates so much mana in the Elves deck
The blue and black sword gives the equipped creature +2/+2 and protection from blue and black, helping your creature to avoid most of the removal spells in the game
So those are five sweet budget cards that deserve more love
The concept is quite similar in Constructed formats, but following the advice of MTG player and mathematician Frank Karsten, the optimal range for adding another color to your deck in a 60-card format is approximately 12 to 13 sources of mana per color