Don't Have

Hexbane Tortoise

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Enlist (As this creature attacks, you may tap a nonattacking creature you control without summoning sickness. When you do, add its power to this creature's until end of turn.)

Turtleshell Changeling

Changeling (This card is every creature type.)
{1}{U}: Switch this creature's power and toughness until end of turn.

Getting

Turtle-Seals

Vigilance (Attacking doesn't cause this creature to tap.)

Armored Whirl Turtle

Tortoise Formation

Creatures you control gain shroud until end of turn. (They can't be the targets of spells or abilities.)

Giant Turtle

This creature can't attack if it attacked during your last turn.

Have

Thriving Turtle

When this creature enters, you get {E}{E} (two energy counters).
Whenever this creature attacks, you may pay {E}{E}. If you do, put a +1/+1 counter on it.

Angler Turtle

Hexproof
Creatures your opponents control attack each combat if able.

Riptide Turtle

Giant Tortoise

This creature gets +0/+3 as long as it's untapped.

Colossal Skyturtle

Flying, ward {2}
Channel — {2}{G}, Discard this card: Return target card from your graveyard to your hand.
Channel — {1}{U}, Discard this card: Return target creature to its owner's hand.

Dragon Turtle

Flash
Drag Below — When this creature enters, tap it and up to one target creature an opponent controls. They don't untap during their controllers' next untap steps.

Tidepool Turtle

{2}{U}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

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.

Blossoming Tortoise

Whenever this creature enters or attacks, mill three cards, then return a land card from your graveyard to the battlefield tapped.
Activated abilities of lands you control cost {1} less to activate.
Land creatures you control get +1/+1.

Wormfang Turtle

When this creature enters, exile a land you control.
When this creature leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Aegis Turtle

Mistford River Turtle

Whenever this creature attacks, another target attacking non-Human creature can't be blocked this turn.

Turtle-Duck

{3}: Until end of turn, this creature has base power 4 and gains trample.