Altar of Transformation

{4}{u}{u}{g}{g} Target planeswalker becomes an
X/X creature with indestructible and hexproof
where X is its loyalty counters. It is still a planeswalker, and keeps its abilities.
{2}{u}{u}{g}{g} Target enchantment becomes an
X/X creature where X is its mana cost. It is still
an enchantment and keeps its abilities.
{2}{u}{u}{g}{g} Target artifact becomes an X/X
creature where X is its mana cost. It is still an artifact and keeps its abilities.