BreezyLimbo
Banned
And poly/hex. You transform their 5/5 to a new 5/5.
Which makes me feel that the Crystal Core is more of a 'map' effect. In that, anything on your side is 5/5, and effects like Ardent Defender/Equality DO affect it since it is layering their affect on top of the Crystal Core one, but things like Hex/Poly don't because it's simply adding another creature to your 'map' and they become affected by the spell.
Like Leeroy Jenkins or Hungry Dragons summons would become 5/5 because the 'map' effect is persistent.