I like the design of your monster a lot, and the composition is strong.
I agree with the above comment that some small bits of complamentary colors would help liven everything up.
To me it looks like the monster just put his hand down there on the ground to keep moving forward. Maybe you could have some bits of dirt and dust flying up?
@caffeinatedbrushes Thank you for your comment !
I've been struggling for some hours when I finally came up with this. I've tweaked the colours, change the sky a bit, bend the trees like there's a quite powerful shock-wave. I'm quite happy with the add of some birds but well not like this. I've also add some dust and cloud for the global depth.
For now I'll leave it like this and will continue thinking of better ways to improve my painting but I feel it's going on the right direction.
Wow this already looks way better! I honestly had no idea the guy in the right corner was there though, he needs to stand out a bit more. The dust by the creature's feet is a nice touch too. Good job it's coming along really nicely!
Thank you ! I'll focus on fixing a lot of my messy stuff for the next step, but I'll take care of my golems soon 
there are troubles with focal point - colors are very similar. this causes a mess. champion is really good (the only thing i would prefer is to do smth with his horn-it looks little bit strange), but he neither attack enemy, nor defend himself or smth.
@darthmorpho Oh sorry about the late response, I reed your reply and then went on something else.
Yes you are right about the colours I need to put a little more variations between the creature and to rock.
And I know this is kind of a gamble but I really don't want to make a fighting character, there are so many other aspect in a war that need to be explored. That's what I went for a flag bearer which objective is to announce an army and make fear upon the enemy. Show the power of earth. I know this is a strange way to do but I'll stick to that.
Anyway thank for your answer <3
Looking awesome 
First really cool design! The shock-wave is a really nice touch and gives the painting a lot of energy! The composition and camera angle are pretty epic as well! My critique would be that the foreground and midground could use some separation, but that might resolve itself already in the refining/detailing process
@ryanchan10101 @darthmorpho @joeypoolart
Thank you guys for the great words and the support <3
I'll put an accent on the separation For/Mid !
If you just change the color of either the foreground or the monster then it will be easier to tell them apart and make the composition stronger.
You could also think about adjusting the value of one or the other.
I like that you didn't go for a straight-up warrior and are attempting a different thing. Could see a flag-bearer announcing the army in a big battle scene like Lord of the Rings.
@caffeinatedbrushes thank you for your comment !
I've done a bit of refinery today, nothing too fancy. I'm thinking of some ways to incorporate more of a feeling that a battle will start soon, I'll work on them a bit 
Absolutely lovely!! Think somewhere in the thread you mentioned MTG, really looks like something that could fit in there reminds me of "Crosan Colossus" by Kev Walker.
I am not exactly sure how, but maybe you could try to make the small golems seem more "moving". Although I can see one of the legs bent at the leftmost one, they still look a little bit stationary.
Thank you so much ! I checked the card and yes I can see what make you think that !
I'll try to make the golems more lively, I also want to add more variation in the design
wow this is beautiful, i love that he literally feels like a part of the earth.also the composition does it a lot of justice
To go off of what hendrix said, I'm wondering if maybe even having the golems looking over their shoulders at the creature, like they're preparing to fire or they're scared would help the narrative you're going for? This is coming together really nice, and Iove your rendering so far! 
@Gil_Ascher @veesketch Thank you so much for your kind words
I will try things with the golems, thank you for the idea !
Wow, I really like the sense of scale in your illustration, very cool!
I also think that linear perspective could use some tweaking. Look at the thickness of the front arm of the creature compared to the back arm - I think that considering the scale of the scene, the front one should appear larger. And maybe it would look better if it was bent a bit in the "elbow" - would convey more of the weight of the creature.
Yes, now that you've mentioned that, you're very right ! Thank you
Very good! I advise you to put different colors in your right arm to avoid confusing it with the environment
