First up, here's a rank of the legendary creatures whose reprints are a price increase, sorted roughly by current price of the original printing: Thrasios, Triton HeroThrasios, Triton Hero Urza, Lord High ArtificerUrza, Lord High Artificer Yawgmoth, Thran PhysicianYawgmoth, Thran Physician Najeela, the Blade-BlossomNajeela, the Blade-Blossom Atraxa, Grand UnifierAtraxa, Grand Unifier Isshin, Two Heavens as OneIsshin, Two Heavens as One Vial Smasher the FierceVial Smasher the Fierce Yuriko, the Tiger's ShadowYuriko, the Tiger's Shadow Kenrith, the Returned KingKenrith, the Returned King Teferi, Mage of ZhalfirTeferi, Mage of Zhalfir K'rrik, Son of YawgmothK'rrik, Son of Yawgmoth Syr Konrad, the GrimSyr Konrad, the Grim Traxos, Scourge of KroogTraxos, Scourge of Kroog Captain Lannery StormCaptain Lannery Storm Danitha Capashen, ParagonDanitha Capashen, Paragon Fynn, the FangbearerFynn, the Fangbearer And the following is the remaining 20 legendary creatures, again sorted roughly by the price of the original printing

Whether by casting huge Eldrazi or looping many spells, the blue mythic card is known to end games
If you control an Eldrazi, you gain 3 life
Dragons Whenever a creature you control leaves the battlefield, this enchantment deals 1 damage to any target
This set is a direct-to-Modern release that'll undoubtedly change the Modern landscape in interesting ways
Lacking any way to mill yourself or discard, Phlage, Titan of Fire's Fury needs to be cast in two stages in most circumstances: you need to cast it from your hand for three mana and sacrifice it, then later escape it from your graveyard so that it can stick around