iPad towerdefense-like 2d game [TOO NEW!!!]

[zDeny]

Hi everyone, the reason why I'm writing here is because, even after hours of searching on the internet and asking friends, I still haven't found the name of this old game.
I used to play it around 2010/14 I guess.
It was in 2d, side view, and you had enemies coming from the right. You had to place troops on the left before the enemies could make it to the other side, taking away all your 5 hearts.
The first troop you used to place was one that produced gems every 15 seconds (?). You needed those gems to place certain troops.
I remember the game's icon being a small, black cube with black eyes and wearing a green, soldier helmet.
Thank you in anticipation, have a good day
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On a final note, the game is NOT plant versus zombies, just specifying this as many of my friends thought this was the game I was referring to

[MrFlibble]

I'm afraid this game is a little bit too new, and out of the scope of this site. Please consider asking around elsewhere, like at Reddit:
https://www.reddit.com/r/tipofmyjoystick/