As long as your devotion to green and blue is less than seven, Kruphix isn't a creature.
You have no maximum hand size.
If you would lose unspent mana, that mana becomes colorless instead.
Kruphix lets you bank unused mana as colorless and never discard, so you ramp hard, draw cards, and stockpile resources until you can unleash an overwhelming X-spell, big creature, or game-ending combo in one massive turn. Early turns are spent ramping and filtering; mid-game you accumulate mana and cards; late game you convert that hoard into a backbreaking play your opponents can't answer.
Effectively removes the maximum hand size, letting you sit on counterspells, removal, and bombs indefinitely
Converts wasted mana into stored colorless, enabling explosive single-turn payoffs with X-spells
Indestructible body that's hard to remove without exile or bounce
Simic colors give the best ramp and card draw in the format
Rewards big mana rocks, ramp dorks, and untap effects beautifully
Slow and durdly; vulnerable to fast aggro and combo decks that close before you assemble your turn
No interaction printed on the commander itself—you must build it in
Can become an arch-enemy magnet once your hand and mana balloon
Mana storage is meaningless without strong payoffs to dump it into
Devotion rarely hits seven, so Kruphix seldom attacks or blocks
Legendary Enchantment Creature — God
