Kruphix, God of Horizons

As a God enters the battlefield, your devotion to its color will determine whether any replacement effects that affect creatures entering the battlefield apply to that God. Because replacement effects are considered before the God is on the battlefield, the mana symbols in its mana cost won't be counted when determining this.

The abilities of Gods function as long as they're on the battlefield, regardless of whether they're creatures.

If a God is attacking or blocking and it stops being a creature, it will be removed from combat. It won't rejoin combat if it resumes being a creature later during that combat.