Sacrifice Scuttling Death: Target creature gets -1/-1 until end of turn.

Soulshift 4 (When this creature dies, you may return target Spirit card with mana value 4 or less from your graveyard to your hand.)

Flash

Vigilance

When Scuttling Sentinel enters, put a +1/+1 counter on another target creature you control. Until end of turn, that creature becomes a blue Crab in addition to its other types and gains hexproof. (It can't be the target of spells or abilities your opponents control.)

Shroud (This creature can't be the target of spells or abilities.)

When Scythe Tiger enters, sacrifice it unless you sacrifice a land.

When Sea Hag enters, creatures your opponents control get -4/-0 until end of turn.

: Target land becomes the basic land type of your choice until end of turn.

Flying, protection from red

Seafloor Debris enters tapped.

: Add .

, Sacrifice Seafloor Debris: Add one mana of any color.

Sacrifice Seal of Cleansing: Destroy target artifact or enchantment.

Sacrifice Seal of Primordium: Destroy target artifact or enchantment.

Reorder your graveyard at random. An opponent chooses a card at random in your graveyard. If it's a creature card, put it onto the battlefield. Otherwise, exile it.

When Search the City enters, exile the top five cards of your library.

Whenever you play a card with the same name as one of the exiled cards, you may put one of those cards with that name into its owner's hand. Then if there are no cards exiled with Search the City, sacrifice it. If you do, take an extra turn after this one.

Flying

When Searchlight Companion enters, create a 1/1 colorless Spirit creature token.

Searing Barb deals 2 damage to any target. If it's a creature, it can't block this turn. Incubate 1. (Create an Incubator token with a +1/+1 counter on it and ": Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

Searing Blaze deals 1 damage to target player or planeswalker and 1 damage to target creature that player or that planeswalker's controller controls.

Landfall — If you had a land enter the battlefield under your control this turn, Searing Blaze deals 3 damage to that player or planeswalker and 3 damage to that creature instead.

Searing Flesh deals 7 damage to target opponent or planeswalker.

Whenever you gain life, you may pay . If you do, Searing Meditation deals 2 damage to any target.

Searing Spear deals 3 damage to any target.

Buyback (You may pay an additional as you cast this spell. If you do, put this card into your hand as it resolves.)

Searing Touch deals 1 damage to any target.

Raid — At the beginning of your end step, if you attacked this turn, create a 1/1 red Goblin creature token.

Whenever Seascape Aerialist or another Ally you control enters, you may have Ally creatures you control gain flying until end of turn.

: Add .

, , Sacrifice a Bird: Draw a card.

Choose up to five worth of modes. You may choose the same mode more than once.

— Put a +1/+1 counter on a creature you control. It gains vigilance and trample until end of turn.

— Choose artifact or enchantment. Destroy all permanents of the chosen type.

— Draw cards equal to the greatest power among creatures you control.

Choose up to five worth of modes. You may choose the same mode more than once.

— Draw a card.

— Choose an artifact or creature you control. Create a token that's a copy of it.

— Return each nonland, nontoken permanent to its owner's hand.

, Exile the top four cards of your library: The next time a source of your choice would deal damage to you this turn, prevent that damage.

Enchant creature or planeswalker you don't control

When Seatower Imprisonment enters the battlefield, conjure a card named Soldiers of the Watch onto the battlefield.

Enchanted permanent can't attack or block, and its activated abilities can't be activated.

Each player returns to the battlefield all artifact, creature, enchantment, and land cards in their graveyard that were put there from the battlefield this turn.

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)

Draw two cards. If you have the city's blessing, draw three cards instead.

Enchant land

When Security Blockade enters, create a 2/2 white Knight creature token with vigilance.

Enchanted land has ": Prevent the next 1 damage that would be dealt to you this turn."

: Create a 1/1 white Soldier creature token. Activate only if you control no creatures and only once each turn.

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Menace

Ward—Pay 3 life. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays 3 life.)

Magecraft — Whenever you cast or copy an instant or sorcery spell, create a 1/1 black and green Pest creature token with "When this creature dies, you gain 1 life."

Flying

Whenever Sedraxis Specter deals combat damage to a player, that player discards a card.

Unearth (: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Reveal the top eight cards of your library. You may put a creature card from among them onto the battlefield. Put the rest into your graveyard.

Ferocious — If you control a creature with power 4 or greater, you may put two creature cards onto the battlefield instead of one.

: Target creature gets +3/+3 until end of turn. Untap that creature.

When Seedguide Ash dies, you may search your library for up to three Forest cards, put them onto the battlefield tapped, then shuffle.

Flying

Whenever Seedpod Squire attacks, target creature you control without flying gets +1/+1 until end of turn.

Cast this spell only during your turn.

Take an extra turn after this one if an opponent cast a blue spell this turn.

Exile the top two cards of your library. Until your next end step, you may play those cards.

Look at the top four cards of your library. You may reveal a creature or land card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

: Draw a card, then discard a card. Activate only if you've cast a noncreature spell this turn.

When Seekers' Squire enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Landfall — Whenever a land you control enters, you may pay . If you do, draw a card.

Buyback (You may pay an additional as you cast this spell. If you do, put this card into your hand as it resolves.)

Target creature gets +3/+0 until end of turn.

Sacrifice an Elemental: Seething Pathblazer gets +2/+0 and gains first strike until end of turn.

Whenever one or more creature cards are put into your graveyard from anywhere, venture into the dungeon. This ability triggers only once each turn. (To venture into the dungeon, enter the first room or advance to the next room.)

Create Undead — Whenever you complete a dungeon, return target creature card from your graveyard to the battlefield.

Flying, vigilance

Flash (You may cast this spell any time you could cast an instant.)

When Seht's Tiger enters, you gain protection from the color of your choice until end of turn. (You can't be targeted, dealt damage, or enchanted by anything of the chosen color.)

When Seismic Elemental enters, creatures without flying can't block this turn.

Trample

, Sacrifice a land: Draw a card.

Mountaincycling (, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Destroy target land. Up to two target creatures can't block this turn.