Evolved Sleeper

{B}: This creature becomes a Human Cleric with base power and toughness 2/2.
{1}{B}: If this creature is a Cleric, put a deathtouch counter on it and it becomes a Phyrexian Human Cleric with base power and toughness 3/3.
{1}{B}{B}: If this creature is a Phyrexian, put a +1/+1 counter on it, then you draw a card and you lose 1 life.

Tenth District Hero

{1}{W}, Collect evidence 2: Tenth District Hero becomes a Human Detective with base power and toughness 4/4 and gains vigilance.
{2}{W}, Collect evidence 4: If Tenth District Hero is a Detective, it becomes a legendary creature named Mileva, the Stalwart, it has base power and toughness 5/5, and it gains "Other creatures you control have indestructible."

Frodo, Sauron's Bane

{W/B}{W/B}: If Frodo is a Citizen, it becomes a Halfling Scout with base power and toughness 2/3 and lifelink.
{B}{B}{B}: If Frodo is a Scout, it becomes a Halfling Rogue with "Whenever this creature deals combat damage to a player, that player loses the game if the Ring has tempted you four or more times this game. Otherwise, the Ring tempts you."

Myth Realized

Whenever you cast a noncreature spell, put a lore counter on this enchantment.
{2}{W}: Put a lore counter on this enchantment.
{W}: Until end of turn, this enchantment becomes a Monk Avatar creature in addition to its other types and gains "This creature's power and toughness are each equal to the number of lore counters on it."

Ascendant Spirit

{S}{S}: This creature becomes a Spirit Warrior with base power and toughness 2/3.
{S}{S}{S}: If this creature is a Warrior, put a flying counter on it and it becomes a Spirit Warrior Angel with base power and toughness 4/4.
{S}{S}{S}{S}: If this creature is an Angel, put two +1/+1 counters on it and it gains "Whenever this creature deals combat damage to a player, draw a card."

The Blackstaff of Waterdeep

You may choose not to untap The Blackstaff of Waterdeep during your untap step.
Animate Walking Statue — {1}{U}, {T}: Another target nontoken artifact you control becomes a 4/4 artifact creature for as long as The Blackstaff of Waterdeep remains tapped. Activate only as a sorcery.

Kellan, Planar Trailblazer

{1}{R}: If Kellan is a Scout, it becomes a Human Faerie Detective and gains "Whenever Kellan deals combat damage to a player, exile the top card of your library. You may play that card this turn."
{2}{R}: If Kellan is a Detective, it becomes a 3/2 Human Faerie Rogue and gains double strike.

Figure of Destiny

{R/W}: This creature becomes a Kithkin Spirit with base power and toughness 2/2.
{R/W}{R/W}{R/W}: If this creature is a Spirit, it becomes a Kithkin Spirit Warrior with base power and toughness 4/4.
{R/W}{R/W}{R/W}{R/W}{R/W}{R/W}: If this creature is a Warrior, it becomes a Kithkin Spirit Warrior Avatar with base power and toughness 8/8, flying, and first strike.

Warden of the First Tree

{1}{W/B}: This creature becomes a Human Warrior with base power and toughness 3/3.
{2}{W/B}{W/B}: If this creature is a Warrior, it becomes a Human Spirit Warrior with trample and lifelink.
{3}{W/B}{W/B}{W/B}: If this creature is a Spirit, put five +1/+1 counters on it.

Sarkhan, the Dragonspeaker

+1: Until end of turn, Sarkhan becomes a legendary 4/4 red Dragon creature with flying, indestructible, and haste. (He doesn't lose loyalty while he's not a planeswalker.)
−3: Sarkhan deals 4 damage to target creature.
−6: You get an emblem with "At the beginning of your draw step, draw two additional cards" and "At the beginning of your end step, discard your hand."