Sliver Construct

A Sliver that joins the tribe without contributing a keyword to it: it has the creature type, so every lord and every shared-ability Sliver still recognizes it, but the body itself brings nothing but a colorless 2/2 to the pile. That makes it the rare member of the family any deck can run regardless of color commitment, which is precisely the point. The tribe's defining gimmick is that abilities granted to one Sliver fan out to all of them, so a vanilla artifact body that costs only generic mana is a clean way to add another beneficiary of the hive's collective buffs without bending your manabase toward five colors. The design logic is closer to a tribal mana rock than to a card with its own plan: it exists to be a warm body wearing the right name tag, picking up haste, pump, evasion, or regeneration from whatever else is on the battlefield. On its own it does nothing a generic 2/2 artifact creature could not, which is the honest read of the card; in a board full of Slivers, it is one more set of stats inheriting everyone else's gifts at the lowest possible color cost.