Chromanticore

The mana cost is the whole joke and the whole problem: five pips, one of each color, an unbroken WUBRG that demands you assemble a perfect five-color manabase before you can cast a 4/4 with a stack of keywords. The bestow version doubles down, asking for that same five-color rainbow plus two generic, and what it buys you is a buff that can outlive a single body. That is the actual design ambition here, and it is more clever than the gold-card flash suggests. Most aura-style effects evaporate when the enchanted creature dies, a one-card-down liability that has haunted every Rancor descendant. Bestow exists to defuse exactly that: cast Chromanticore onto a creature, and if that creature dies, the enchantment unattaches and stands up as its own 4/4 instead of going to the graveyard. The card was the most ornate showcase the mechanic ever got, a single permanent that piles flying, first strike, vigilance, trample, and lifelink onto a host and then refuses to die with it. The five-color cost is the tax the keyword stack pays for; whether any deck can actually afford that tax is a question every printing has left unanswered. As a piece of color-identity design it is maximal by definition: there is no creature in the game with a broader identity, and few that ask so much for so total a payoff.