[+1]: Create a 1/1 white Soldier creature token with lifelink.
[−2]: Put two +1/+1 counters on target creature. It becomes an Angel in addition to its other types and gains flying.
[−6]: Return all nonland permanent cards with mana value 3 or less from your graveyard to the battlefield.
For the last ability, if a card in your graveyard has {X} in its mana cost, X is 0.
If the target of the second ability stops being a creature after the ability has resolved, it will also stop being an Angel until it becomes a creature again, if applicable.
The second ability doesn’t have a duration. It lasts until the creature leaves the battlefield.