As Citadel Siege enters the battlefield, choose Khans or Dragons.
• Khans — At the beginning of combat on your turn, put two +1/+1 counters on target creature you control.
• Dragons — At the beginning of combat on each opponent's turn, tap target creature that player controls.

Kicker (You may pay an additional as you cast this spell.)
When Citanul Woodreaders enters the battlefield, if it was kicked, draw two cards.

Crimson Muckwader gets +1/+1 as long as you control a Swamp.
: Regenerate Crimson Muckwader. (The next time this creature would be destroyed this turn, it isn't. Instead tap it, remove all damage from it, and remove it from combat.)

Choose a Giant creature you control. It deals damage equal to its power to target creature.

Destroy target green or white creature.

Enchant creature
Prevent all damage that would be dealt by enchanted creature.

Destroy target artifact or land.

For each tapped nonland permanent target opponent controls, search that player's library for a card with the same name as that permanent. Put those cards onto the battlefield under your control, then that player shuffles their library.
Suspend 3— (Rather than cast this card from your hand, you may pay and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, cast it without paying its mana cost.)

Flying
: Dragon Whelp gets +1/+0 until end of turn. If this ability has been activated four or more times this turn, sacrifice Dragon Whelp at the beginning of the next end step.

Flying, deathtouch
When Dragonlord Silumgar enters the battlefield, gain control of target creature or planeswalker for as long as you control Dragonlord Silumgar.

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Reach
Other Elf creatures you control get +1/+1.
Whenever Dwynen, Gilt-Leaf Daen attacks, you gain 1 life for each attacking Elf you control.

Changeling (This card is every creature type.)
Creatures target player controls get -2/-0 and lose all creature types until end of turn.

[+2]: Put a +1/+1 counter on each of up to two target creatures.
[−2]: Search your library and/or graveyard for a card named Sunlit Hoplite and put it onto the battlefield. If you search your library this way, shuffle it.
[−8]: Until end of turn, creatures you control gain flying and get +X/+X, where X is your devotion to white.

Etched Monstrosity enters the battlefield with five -1/-1 counters on it.
, Remove five -1/-1 counters from Etched Monstrosity: Target player draws three cards.

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Artifact spells you cast cost less to cast.

, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle your library.

: Add one mana of any color that a land an opponent controls could produce.

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Return target nonland permanent to its owner's hand. If you have the city's blessing, you may put that permanent on top of its owner's library instead.