When this creature enters, target creature you control gets +2/+2 until end of turn.
Plainscycling {2}

Flying
When Gereishin enters, if it was cast, you may cast a Dragon spell or a spell with mana value 6 or less from your hand without paying its mana cost.
Once during each of your turns, when you spend less mana to cast a spell than its mana value, you may have Gereishin deal damage to up to one target creature equal to the difference.

Flying
Whenever you cast a spell from exile, this creature deals damage equal to that spell's mana value to any target.

{2}{G}, {T}: Mill two cards, then create a tapped 1/1 white Citizen creature token.
{6}{G}{G}, {T}: Mill two cards, then create a tapped X/X colorless Construct artifact creature token, where X is the number of creature and/or enchantment cards in your graveyard.

Flying
If a Dragon you control would deal damage to an opponent, it deals that much damage plus 1 instead.
{2}{U}{R}: Transform Iviana's Spellmaw.

Flying, trample
If a source you control would deal damage to an opponent or a permanent an opponent controls, you may have it deal twice that much damage instead if it's a Dragon or Iviana planeswalker. Otherwise, it deals that much damage plus 2 instead.

King of Currents can't attack unless there are six or more cards in your graveyard.
Surface {4}{U}{U}

Flying
Whenever one or more creatures you control become tapped, tap up to one target creature an opponent controls.

Ninjutsu {2}{G}{U}
Whenever this creature deals combat damage to a player, you may search your library for a land card, put it onto the battlefield tapped, then shuffle. That land becomes a 4/4 Dragon creature in addition to its other types.

Haste
Landfall — Whenever a land you control enters, Leaping Hatchling gains flying and trample until end of turn.