You may sacrifice four Eldrazi Spawn rather than pay this spell's mana cost.
Annihilator 1

At the beginning of combat on your turn, equipped creature or a creature you control named Vecna gets +X/+X until end of turn, where X is the number of cards in your hand.
Equip — Pay 1 life for each card in your hand.
Equip

, : Create a 2/2 colorless Homunculus creature token. It must be represented by a unique hand and two fingers at all times, or it ceases to exist.

Equipped creature has ": Put an aim counter on Hankyu" and ", Remove all aim counters from Hankyu: This creature deals damage to any target equal to the number of aim counters removed this way."
Equip

Spells you cast cost less to cast.

Starting & Max Hand Size: +1
Starting Life: -5

: Add .
, : Target creature gains haste until end of turn.
, : If you both own and control this land and a creature named Hanweir Garrison, exile them, then meld them into Hanweir, the Writhing Township.

Trample, haste
Whenever Hanweir attacks, create two 3/2 colorless Eldrazi Horror creature tokens that are tapped and attacking.

Names — Happy / Dead / Squirrel
Art — Top hat / Kitten / Garruk plushie
2 — : Add . Spend this mana only to cast noncreature spells.
3 — Infect.
2 — 3/2
4 — 4/7

Whenever you crank Hard Hat Area, roll two six-sided dice. Hard Hat Area assembles a number of Contraptions equal to the difference between those results. (To assemble a Contraption, put the top card of your Contraption deck face up onto one of your sprockets.)

When this creature dies, return it to the battlefield transformed under your control.

: Add .
, Pay 1 life: Add .
, , Sacrifice a Desert: Target creature gets +3/+3 until end of turn. Activate only as a sorcery.

At the beginning of your upkeep, exile the top card of your library face down. You may look at that card for as long as it remains exiled.
Once during each of your turns, you may play a land or cast a spell from among the cards exiled with this permanent without paying its mana cost.

Equipped creature has vigilance, trample, and haste.
Equip

: Add .
, , Sacrifice this land: Return a creature card at random from your graveyard to your hand.

Defender, first strike

Visit — Return target creature card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of your next end step.

This land enters tapped.

Equipped creature gets +4/+4.
: Until end of turn, this permanent becomes a 4/4 Spirit artifact creature that's no longer an Equipment. Activate only if you control no creatures.
Equip

This land enters tapped unless you control two or more other lands.
: Add or .

: Add or .
, Pay 1 life: Add , , or .
: Put seven +1/+1 counters on this artifact. It becomes a 0/0 Spirit creature in addition to its other types. Activate only once.

This land enters tapped.
: Add or .

: Add .
: Add one mana of any color. Spend this mana only to cast a Dragon creature spell.
, , Sacrifice this land: Return target Dragon creature card or Ugin planeswalker card from your graveyard to your hand.

: Add .
, : Investigate.
At the beginning of your end step, if you sacrificed three or more Clues this turn, transform Havengul Laboratory.