Moonveil Dragon

Flying
{R}: Each creature you control gets +1/+0 until end of turn.

Teeka's Dragon

Flying; trample; rampage 4 (Whenever this creature becomes blocked, it gets +4/+4 until end of turn for each creature blocking it beyond the first.)

Alabaster Dragon

Flying
When Alabaster Dragon dies, shuffle it into its owner's library.

Palladia-Mors

Flying, trample
At the beginning of your upkeep, sacrifice Palladia-Mors unless you pay {R}{G}{W}.

Black Dragon

Flying
Acid Breath — When Black Dragon enters, target creature an opponent controls gets -3/-3 until end of turn.

Catacomb Dragon

Flying
Whenever Catacomb Dragon becomes blocked by a nonartifact, non-Dragon creature, that creature gets -X/-0 until end of turn, where X is half the creature's power, rounded down.

Silver Drake

Flying
When Silver Drake enters, return a white or blue creature you control to its owner's hand.

Viral Drake

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{3}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Tempest Drake

Lotus Guardian

Lightning Dragon

Flying
Echo {2}{R}{R} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
{R}: Lightning Dragon gets +1/+0 until end of turn.

Pendrell Drake

Flying
Cycling {2} ({2}, Discard this card: Draw a card.)

Rakdos Drake

Flying
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Mist Dragon

{0}: Mist Dragon gains flying. (This effect lasts indefinitely.)
{0}: Mist Dragon loses flying. (This effect lasts indefinitely.)
{3}{U}{U}: Mist Dragon phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before you untap during your next untap step.)

Clockwork Dragon

Flying
Clockwork Dragon enters with six +1/+1 counters on it.
Whenever Clockwork Dragon attacks or blocks, remove a +1/+1 counter from it at end of combat.
{3}: Put a +1/+1 counter on Clockwork Dragon.

Wind Drake

Iridescent Drake

Flying
When Iridescent Drake enters, put target Aura card from a graveyard onto the battlefield under your control attached to Iridescent Drake.

Ebon Dragon

Flying
When Ebon Dragon enters, you may have target opponent discard a card.

Peregrine Drake

Flying
When Peregrine Drake enters, untap up to five lands.

Covetous Dragon

Flying
When you control no artifacts, sacrifice Covetous Dragon.

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Azure Drake

Shivan Dragon

Flying (This creature can't be blocked except by creatures with flying or reach.)
{R}: Shivan Dragon gets +1/+0 until end of turn.

Chromium

Flying
Rampage 2 (Whenever this creature becomes blocked, it gets +2/+2 until end of turn for each creature blocking it beyond the first.)
At the beginning of your upkeep, sacrifice Chromium unless you pay {W}{U}{B}.

Shrieking Drake

Flying
When Shrieking Drake enters, return a creature you control to its owner's hand.

Nicol Bolas

Flying
At the beginning of your upkeep, sacrifice Nicol Bolas unless you pay {U}{B}{R}.
Whenever Nicol Bolas deals damage to an opponent, that player discards their hand.