Mass of Remains's power is equal to the total number of permanent cards you own in your graveyard and in exile.
Spellcharge 3

Target creature you control gets +2/+1 until end of turn. It fights up to one target creature you don't control.

Ninjutsu {2}{G}
When this creature enters, creatures you control gain trample until end of turn.

Vigilance
Flow — {7}{W}: Tap all creatures target player controls.

Double strike
Whenever an enchantment you control enters, you may create a token that's a copy of it, except the token isn't legendary and has exalted. Do this only once each turn.

Whenever you cast a noncreature spell, put an exalted counter on this enchantment.
Whenever a creature you control attacks, draw X cards if its power is greater than 7, where X is the difference.

Matter Harvester has protection from mana values less than the number of artifacts you control.
Whenever a nonland permanent you don't control leaves the battlefield, create a 1/1 colorless Cyborg artifact creature token.

This land enters tapped unless you control one or fewer other lands.
{T}: Add {R} or {G}.
Cycling {2}

Target creature gains indestructible until end of turn. Teach it lifelink.

You gain 2 life and draw two cards.
Cycling {2}

Create two 1/1 blue Wizard creature tokens with prowess.

When this creature enters, create X green Subroutine enchantment tokens named MOUNT with “Whenever this Subroutine runs, target creature you control gets +2/+2 until end of turn.”

Whenever you draw your second card each turn, scry 1 then put a +1/+1 counter on Melancholic Oracle.

When Mellan, Defense Attorney enters, make a pledge.
{T}: Choose a color from among other permanents you control. Another target creature you control gains hexproof from that color until end of turn. It can't be blocked by creatures of that color this turn.

Target artifact or creature's owner puts it on the top or bottom of their library.
Flashback {5}{U}{U}

Deathtouch
Whenever you cache a card, this creature gets +2/+2 and gains indestructible until end of turn.

Whenever this creature deals combat damage to a player, create an X/X colorless Construct artifact creature token, where X is 1 plus the number of counters on this creature.
{1}, Sacrifice an artifact or enchantment: Put a +1/+1 counter on this creature. It gains trample until end of turn.

When Menelaia enters, put a +1/+1 counter on up to two target creatures.
{1}, Remove a +1/+1 counter from another creature you control: That creature gain indestructible until end of turn. Tap it.

Revered
Whenever this creature deals combat damage to a player, create a 1/1 green Spirit creature token.

Flying
{5}: Draw a card. Activate only if your devotion to blue is three or greater.

When Merciless Headsman enters, create a 2/2 colorless Minion creature token with decayed.
{1}{B}, Sacrifice another creature: Draw a card.

Exalted
When this creature enters, each player sacrifices a creature or planeswalker of their choice.

Trample
Mercurial Wright gets +1/+0 for each other artifact you control.
{2}: Target permanent becomes an artifact in addition to its other types until end of turn.

{1}{U/R}, {T}: Tap target creature, then gain control of it until end of turn. Activate only as a sorcery.

{W}, {T}: Tap target creature. Activate only as a sorcery.
{6}{W}{W}, {T}: Tap all creatures you don't control. Activate only as a sorcery.