When Bilbo Baggins enters, draw a card.

X can't be 0.
Target spell's controller exiles it with X delay counters on it.
At the beginning of each of that player's upkeeps, if that card is exiled, remove a delay counter from it. If the card has no delay counters on it, the player puts it onto the stack as a copy of the original spell.

All damage that would be dealt this turn to target creature you control by a source of your choice is dealt to another target creature instead.

When this creature dies, recruit. (Draw a card, then discard a card. If you discarded a nonland card, create a 1/1 white Human Soldier creature token.)

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Exile target creature. Put two loyalty counters on a planeswalker you control.

This land enters tapped.
: Add or .
, , Sacrifice this land: Put two +1/+1 counters on target Human you control. Activate only as a sorcery.

Return target instant or sorcery card from your graveyard to your hand.

This artifact enters tapped.
, , Sacrifice this artifact: Add X mana in any combination of colors.
When this artifact is put into a graveyard from the battlefield, draw a card.

Return target creature card from your graveyard to your hand.

Morph (You may cast this card face down as a 2/2 creature for . Turn it face up any time for its morph cost.)
Whenever this creature or another creature you control is turned face up, untap that creature.

When this creature enters, return to your hand the creature card in your graveyard with the greatest power. If two or more cards are tied for greatest power, you choose one of them.

, Exile this Vehicle and four other artifact creatures and/or Vehicles you control: Create Mechtitan, a legendary 10/10 Construct artifact creature token with flying, vigilance, trample, lifelink, and haste that's all colors. When that token leaves the battlefield, return all cards exiled with this Vehicle except this card to the battlefield tapped under their owners' control.
Crew 2

, : Another target creature you control with power 2 or less can't be blocked this turn.

Chroma — Umbra Stalker's power and toughness are each equal to the number of black mana symbols in the mana costs of cards in your graveyard.

Flying
When this creature enters, you may search your library for an artifact card, exile it, then shuffle.
When this creature dies, you may put the exiled card into its owner's hand.

Flying, trample
This creature attacks each combat if able.
Whenever this creature deals damage, you lose that much life.

Until end of turn, target creature gets +3/+3, up to one other target creature gets +2/+2, and up to one other target creature gets +1/+1. Those creatures gain vigilance until end of turn.

Mutate (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Whenever this creature mutates, other creatures you control get +X/+X until end of turn, where X is the number of times this creature has mutated.

As an additional cost to cast this spell, discard a card.
Draw two cards.
Flashback (You may cast this card from your graveyard for its flashback cost and any additional costs. Then exile it.)