Thrun, Denied Death

Legendary Creature -- Troll Zombie (M)
Whenever Thrun, Denied Death dies, if it had four or fewer -1/-1 counters on it, return it to the battlefield with a number of -1/-1 counters on it equal to the number of -1/-1 counters that was on it plus one.
5/5

There's gotta be a better way to template this, but I've wasted too much time on it already.

Mirran Resistance
Creature — Human Warrior
Persevere (If this creature would be destroyed, exile it instead. At the beginning of your next declare attackers step, put it onto the battlefield tapped and attacking and sacrifice it at the beginning of your next end step. It loses persevere.)
Whenever Mirran Resistance enters the battlefield, creatures you control get +1/+0 until end of turn.
3/1

Vessel of Urabrask

Artifact Creature -- Construct (C)
Haste
Vessel of Urabrask enters the battlefield with a -1/-1 counter on it.
Purify (: Replace all -1/-1 counters on this creature with +1/+1 counters on it. Purify as a sorcery.)
3/3

Hypothetical Mirrodin Pure mechanic?

Verdigris Lair
Land
Verdigris Lair enters the battlefield with a -1/-1 counter on it.
, Pay 1 life: Add or .
: Add or . Activate this ability only if there is a +1/+1 counter on Verdigris Lair.
Purify
In the end, Glissa saved Mirrodin again, and she went unthanked, again.

Next is Kamigawa.

Snow-Fur, Kitsune Poet —
Legendary Creature — Fox Noble Monk
Other creatures you control with converted mana cost 2 get +2/+2.
2/2

Tale of the Found Princess
Enchantment — Saga
I - Search your library for a Moonfolk creature card, put it onto the battlefield, then shuffle your library.
II - Exchange control of the Moonfolk creature card put onto the battlefield with target creature.
III - Return the Moonfolk creature put onto the battlefield to its owner's hand.

Gaping-Maw Kami —
Creature — Spirit (C)
When Gaping-Maw Kami enters the battlefield, destroy target non-Spirit creature.
"I'm not scared of what I'll find at the bottom. I'm scared that there is no bottom."
—Toshiro Umezawa
1/3

Samurai of Blood Honor
Creature — Ogre Samurai
Haste
When Samurai of Blood Honor dies, add . This mana doesn't empty until end of turn. Spend this mana only to cast Demon spells or to activate abilities from Demon sources.
"For you, honor is something paid with only one life. My code demands many more."
4/2

Soulbound Replenisher
Creature - Spirit (U)
Soulshift 3 (When this creature dies, you may return target Spirit card with converted mana cost 3 or less from your graveyard to your hand.)
Each creature card in your graveyard is a Spirit in addition to its other types.
Life is life, no matter the source.
3/4

The Peach Boy
Enchantment — Saga
I - Create a Food token.
II - At beginning of your next end step, search your library for a creature card with converted mana cost X or less, where X is the amount of life you gained this turn. Put it onto the battlefield, then shuffle your library.
III - Target creature you control gains indestructible until end of turn if it's legendary. Then, it fights up to one target creature you don't control.

Bridge Between Worlds
Land (R)
Bridge Between Worlds enters the battlefield tapped unless you control a Spirit.
: Add .
, Pay 1 life: Add one mana of any color.

Next is Ravnica.

Skyscribe
Creature — Human Advisor Spellshaper
Flying
, , Discard a card: Each player draws X cards.
"The law is written into the sky, clear as day. Failure to comply is inexcusable."
1/3

Moroii of Memories
Creature — Vampire Spellshaper
, , Discard a card: Exile up to four cards in a single graveyard.
, , Discard a card: Search your library for a card with converted mana cost of exactly 2, reveal it, put it into your hand, then shuffle your library.
"What you thought was, was not. What you thought was not, was."
2/2

Revenant of Benediction
Creature — Spirit Cleric
, , Discard a card: You gain 1 life for each player. When up to one target creature dies, you gain 1 life for each player.
0/4

Thunderspine Piker

Creature -- Viashino Warrior (U)
Galvanize (The first instant or sorcery spell you cast on your turn costs less.)
Whenever you cast an instant or sorcery spell, Thunderspine Piker gains first strike until end of turn.
3/1

Cultivator in the Dark
Creature — Elf Spellshaper
, , Discard a card: Target creature gets -1/-1 until end of turn.
If you would draw a card and Cultivator in the Dark is untapped, instead you may pay , tap Cultivator in the Dark, and put the top three cards on your library into your graveyard. When you do, target creature gets -1/-1 until end of turn.
1/1

Marika, League Exile

Legendary Creature -- Human Wizard
2/3
Instant and sorcery spells you cast have replicate .
Whenever an instant or sorcery spell you control resolves, Marika, League Exile deals 1 damage to any target and you gain 1 life.

Experimental Jetpack
Artifact
Whenever you cast an instant or sorcery spell, put a charge counter on Experimental Jetpack.
, Remove X charge counters from Experimental Jetpack: Equipped creature gets +X/+0 and gains flying and first strike until end of turn.
: Double the number of charge counters on Experimental Jetpack
Equip

Jace's Sanctum
Legendary Land
Jace's Sanctum enters the battlefield tapped unless a player has 10 or more cards in your graveyard or you control a Jace planeswalker.
: Add . If this mana is spent to cast a Jace planeswalker spell, that planeswalker enters the battlefield with an additional loyalty counter.
, : Look at the top two cards on your library. Put one on top of your library and the other in your graveyard.

Next is Dominaria.