My most competitive version of Mono-Green for Modern.
So there are really two ways to approach what counts as Modern mono-green 'stompy' these days, and it is predicated on one question - to Hierarch or not to Hierarch? I've tried the former version in my deck Don't Let 'Em Breathe (Fat) and it's how I instinctively want to play the archetype - tons of three CMC creatures to drop as a second-turn play off the Hierarch and to hit big on turn three with a CoCo... but as much fun as that is, I've come to the conclusion that it's the wrong way to go. Sure, it can win, and it can be really dominant when it really gets rolling - IF it gets rolling. More often than not, that Hierarch ends up being the Achilles Heel of the deck rather than its strength, because too much depends on the squishiest of squishies. I play him, he inevitably gets bolted or darted or pushed and then I'm sitting around without even being able to make an attack until turn four, by which time my opponent has his own game plan well in hand.
So instead I'm going with more of a weenie-ish approach, taking advantage of the traditional 1 CMC, +1/+1 counter staples and highly efficient creatures like Hexdrinker, Narnam Renegade, Strangleroot Geist and Werewolf Pack Leader. For my only 3 CMC creatures, I keep the ubiquitous Steel Leaf Champion and the much more rarely seen Gourndbreaker. This gives me a very smooth mana curve, under-costed creatures that can be difficult to deal with and more importantly gives me a wider spread of creatures on the board, opening the door for a more effective Aspect of Hydra when the time comes. My only other non-creature spells are 2x Rancor and 1x Sylvan Anthem, both of which have proven their worth time and again. Every single card in the deck builds maximum devotion for when Aspect goes off.
This particular build is resilient against a lot of the issues that often plague mono-green and allows you to consistently put pressure on and keep it one from the get-go. Thus far the results have been excellent, but, as always, any thoughts and suggestions are welcome.
EDIT: I'm thinking about making a few land changes - dropping the Narnam Renegade, replacing it with something like a fourth Pelt Collector, a fourth Experiment One, a fourth Hexdrinker and a either a Yorvo or a Rhonas. Without the need for a trigger for the Renegade, I drop the fetch lands and go with 2x Nykthos, Shrine to Nyx, 2x Lair of the Hydra, 2x Boseiju, Who Endures and 13x Forest. We'll see how it goes.