Imperial Outrider
Four mana buys a 1/5 with no text, which tells you exactly what the design brief was: a creature that exists to be blocked behind and to carry a word on its type line. The five toughness is a genuine wall, stonewalling most early ground attackers and shrugging off the burn and combat math that kills lesser blockers, but the body has no ambitions past that. There is no combat trick, no activated ability, no evasion, nothing that turns the wall into a threat. Knight and Human are the only levers it pulls, so its entire purpose is tribal: it feeds whatever anthem or lord happens to reward those creature types while contributing nothing on its own. At its cost it sits toward the top of a Knights curve rather than filling out the cheap slots, which makes the plainness a harder sell, since four mana is prime real estate a tribal deck usually wants spent on a payoff, not a body that only blocks. What it offers is durability and a relevant tag, the kind of common-rarity role-player a tribal shell tolerates when it needs a wall that also counts. Measured against the field of four-mana white creatures, it is deliberately bare: a defensive brick everywhere, and a Knight only where being a Knight is worth four mana.
