You may have Spark Double enter as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.
As an additional cost to cast this spell, discard a card. Protection from planeswalkers {1}: Sparkhunter Masticore deals 1 damage to target planeswalker. {3}: Sparkhunter Masticore gains indestructible until end of turn.
{R}, {T}, Discard a card: Create a 3/1 red Elemental creature token named Spark Elemental. It has trample, haste, and "At the beginning of the end step, sacrifice Spark Elemental."
When you encounter Spatial Merging, reveal cards from the top of your planar deck until you reveal two plane cards. Simultaneously planeswalk to both of them. Put all other cards revealed this way on the bottom of your planar deck in any order.
Sacrifice a creature: Put a charge counter on Spawning Pit. {1}, Remove two charge counters from Spawning Pit: Create a 2/2 colorless Spawn artifact creature token.
{1}, {T}, Sacrifice a creature: Seek a creature card with mana value equal to 1 plus the sacrificed creature's mana value and put that card onto the battlefield. That creature is a Phyrexian in addition to its other types. Activate only as a sorcery.
Vigilance, lifelink {T}: Create a 4/4 white Angel creature token with flying. Activate only if you have at least 7 life more than your starting life total and only as a sorcery.
When Specimen Collector enters, create a 1/1 green Squirrel creature token and a 0/3 blue Crab creature token. When Specimen Collector dies, create a token that's a copy of target token you control.
Flying When Specter of Mortality enters, you may exile one or more creature cards from your graveyard. When you do, each other creature gets -X/-X until end of turn, where X is the number of cards exiled this way.
Flash Flying When Spectral Adversary enters, you may pay {1}{U} any number of times. When you pay this cost one or more times, put that many +1/+1 counters on Spectral Adversary, then up to that many other target artifacts, creatures, and/or enchantments phase out.