Lazul, Herald's Mercy

Ascension (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
{g} Regenerate target creature - The regenerated creature has a -1/-1 counter for each time it's been regenerated this way

At the end of your turn, return target creature from your grave to your hand. if you have the city's blessing, return it to the battlefield instead.