Mahamoti Djinn

The flagship vanilla flier of the original game, and for a long stretch the rate everyone measured big blue creatures against. Alpha set the slope deliberately steep: blue paid full freight for evasive bodies, and six mana for a 5/6 flier with no abilities beyond the keyword was the ceiling of what the color was allowed to put into play. The design logic was that blue's creatures should feel like summoned outsiders (rare, expensive, unbeatable in the air once they landed) rather than efficient board presence. Everything blue has done in the fatty-flier slot since has answered to that baseline. Morphling added untargetability and combat tricks at the same cost. Keiga, the Tide Star folded in removal. Aetherling exiled itself to dodge sweepers. Each successor justified its mana by stapling on what the Djinn refused to do, which is the clearest sign of how the original was priced: as a finisher whose only job was to be bigger in the air than anything else on the table, and to cost enough that you felt the summoning. The card reads quaint now because the rate has been lapped many times over, but the lineage of expensive blue evasion flows directly out of this stat line.