On the lawless frontier, death can come in a flash.
Najash Battle Priest
Creature- Snake Shaman
Whenever you cast an instant or a spell with flash, you may put a +1/+1 counter on Najash Battle Priest.
When Intrepid Pioneer enters the battlefield, you may put a basic land card from your hand onto the battlefield tapped.
Najash Medicine Man
When Najash Medicine Man enters the battlefield, regenerate target creature.
Creature- Snake Warrior
Whenever you cast an instant or a spell with flash, Elusive Najash gains shroud until end of turn.
Creature- Snake Warrior
[Hunted Aurochs- http://community.wizards.com/magicthegathering/wiki/Guns_for_Hire-_Challenge_2]
Whenever Hunted Aurochs attacks, it gets +1/+0 until end of turn for each other attacking Aurochs.
When Hunted Aurochs is put into a graveryard from the battlefield, you gain 2 life.
Creature- Snake Warrior Druid
When Najash Guerillas enters the battlefield, destroy target artifact or enchantment.
Whenever you cast an instant or a spell with flash, Sandtiller Wurm gets +2/+2 until end of turn.
[Coup Counting- http://community.wizards.com/magicthegathering/wiki/Old_Challenge_2_Design_Skeleton_Discussion]
Whenever enchanted creature deals combat damage to a creature, put a +1/+1 counter on it.
[Reprint- Time Spiral]
Put a 1/1 green Saproling creature token onto the battlefield.
Prevent all combat damage that would be dealt by creatures with flying this turn.
Until end of turn, target creature gets +2/+2 for each instant you cast this turn.
Choose target creature you control and target creature an opponent controls. Each of those creatures deals damage equal to its power to the other.
You gain 2 life for each tapped creature you control.
Stake a Claim
Search your library for a basic land card and put that card onto the battlefield tapped. Then shuffle your library.
Draw a card and then discard a card.
[Serpents in the Soil- http://community.wizards.com/magicthegathering/wiki/Guns_for_Hire-_Challenge_2]
Put two 1/1 green snake creature tokens onto the battlefield.
Retaliate- If a creature under your control was destroyed this turn, put four 1/1 green snake creature tokens onto the battlefield instead.
I made a major change to my theme this week by choosing to focus on instants and spells with flash. My old mechanics started as an attempt to convey surprise and speed, but it has become clear to me that they were no fulfilling that role adequately. I think the new theme should be more fun to play and will truly do this setting justice.
Green is represented on Deadsands by settlers, hunters, trappers, and frontiersman. Green is also represented by the Najash, a reclusive tribe of snake people that is focused on stopping the technological and industrial expansion of the frontier.
Showdown was left out of this submission because it still needs more work and I'm not sure if it belongs at common. My last attempt at the mechanic was "Showdown- If you cast the most spells this turn, GREATER EFFECT". This version was designed to go with the new theme.