
Dauntless River Marshal | Creature | Human Soldier | Dauntless River Marshal gets +1/+1 as long as you control an Island.
{3}{U}: Tap target creature. | Mark Winters

Chief Engineer | Creature | Vedalken Artificer | Artifact spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting an artifact spell pays for {1} or one mana of that creature's color.) | Steven Belledin

Diffusion Sliver | Creature | Sliver | Whenever a Sliver creature you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}. | Trevor Claxton

Quickling | Creature | Faerie Rogue | Flash (You may cast this spell any time you could cast an instant.)
Flying
When Quickling enters the battlefield, sacrifice it unless you return another creature you control to its owner's hand. | Clint Cearley

Research Assistant | Creature | Human Wizard | {3}{U}, {T}: Draw a card, then discard a card. | Svetlin Velinov

Welkin Tern | Creature | Bird | Flying (This creature can't be blocked except by creatures with flying or reach.)
Welkin Tern can block only creatures with flying. | Austin Hsu