Hydra staples

[LadyGrixis]

But if you're ramping, like {Karametra's Acolyte}, {Sylvan Caryatid}, etc., then Polukranos is a MUST. Forget the XX cost, he's a bomb you can ramp into by Turn 3 and people either have to deal with him or waste counters/burn/kill spells on him. Love him.

[Gorzo]

I threw together a green/red hydra deck not long ago that actually runs pretty well.

It's all about the mana ramp
{Elvish Mystic}
{Karametra's Acolyte}
{Zhur-Taa Druid}

The bombs
{Kalonian Hydra}
{Mistcutter Hydra}
{Savageborn Hydra}
{Polukranos, World Eater}
{Ruric Thar, the Unbowed}
{Akroan Colossus}

And some support
{Ghor-Clan Rampager} (just for Bloodrush)
{Bow of Nylea}
{Nylea, God of the Hunt}

[rarehuntertay]

If its any format, ramp a huge  {Mistcutter Hydra} and then cast  {Sway of Illusion} making all their monsters blue...

[FlickerYourOwnIdentity]

If its any format, ramp a huge  {Mistcutter Hydra} and then cast  {Sway of Illusion} making all their monsters blue...

Lol, legacy hydras