Zynga's ecologically sound tower offense game Eden to Green live in Canada

Zynga's decision to start publishing mobile games kicked off with the action RPG Horn back in August 2012.

Impressive as it was, however, the $6.99 premium game didn't really mesh with Zynga's free-to-play audience.

It's published another five titles since then, but it's looking to freemium release Eden to Green to provide its first breakout hit.

Developed by well regarded Japanese studio iNiS Corporation (best know for rhythm action titles like Elite Beat Agents on DS), the Unreal-powered game brings 3D graphics, turn-based dynamics, and a more expansionist edge to the tower defence gameplay of Plants vs. Zombies.

As the title suggests, it also has a strong ecological theme, placing you on the side of nature, looking to make green the territory that has been invaded and polluted by nasty, oily machinery.

Each level starts with you defending a small circle of green grass, with a tree in its center.

Marshalling various resources, you place plant-based units, which offer different attributes, anywhere in the green area.

Some plants are strong in defence and attack - whether melee or ranged - while others will grow the green area under your control.

This is important, because the larger the green area, the more energy (or euphoria) you get at the end of each turn, and the more freedom you have to place your units on each map.

In terms of overall scope, there are 47 levels across each of 4 themed worlds.

As you play through each one, you'll get to unlock more of the 100 plant types, as well as levelling each type up, and cloning them so you can plant them more regularly during each battle.

This nurturing gameplay is subtle, but actually provides a lot of the game's deeper strategy.

Also, in keeping with Zynga's social expertise, you can borrow one plant per stage from your friends, highlighting the gifting mechanism that made games like FarmVille so popular.

We expect there will be a multiplayer mode added at some point too, but there aren't many details on that as yet.

Currently available in the Canadian App Store/Google Play for testing, Eden to Green will be released globally for iOS and Android soon.