Towering Titan

Towering Titan enters with X +1/+1 counters on it, where X is the total toughness of other creatures you control.
Sacrifice a creature with defender: All creatures gain trample until end of turn.

Levitation

Tower Defense

Creatures you control get +0/+5 and gain reach until end of turn.

The Pride of Hull Clade

This spell costs {X} less to cast, where X is the total toughness of creatures you control.
Defender
{2}{U}{U}: Until end of turn, target creature you control gets +1/+0, gains "Whenever this creature deals combat damage to a player, draw cards equal to its toughness," and can attack as though it didn't have defender.

Zopandrel, Hunger Dominus

Reach
At the beginning of each combat, double the power and toughness of each creature you control until end of turn.
{G/P}{G/P}, Sacrifice two other creatures: Put an indestructible counter on Zopandrel, Hunger Dominus. ({G/P} can be paid with either {G} or 2 life.)

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Charix, the Raging Isle

Spells your opponents cast that target Charix, the Raging Isle cost {2} more to cast.
{3}: Charix gets +X/-X until end of turn, where X is the number of Islands you control.

Unnatural Growth

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

Hover Barrier

Bedrock Tortoise

During your turn, creatures you control have hexproof.
Each creature you control with toughness greater than its power assigns combat damage equal to its toughness rather than its power.

Biomancer's Familiar

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.
{T}: The next time target creature adapts this turn, it adapts as though it had no +1/+1 counters on it.

Slagwurm Armor

Equipped creature gets +0/+6.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Assault Formation

Each creature you control assigns combat damage equal to its toughness rather than its power.
{G}: Target creature with defender can attack this turn as though it didn't have defender.
{2}{G}: Creatures you control get +0/+1 until end of turn.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Shield Sphere

Defender
Whenever Shield Sphere blocks, put a -0/-1 counter on it.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Tree of Redemption

Defender
{T}: Exchange your life total with Tree of Redemption's toughness.

Meekstone

Creatures with power 3 or greater don't untap during their controllers' untap steps.