The art on the back-side is cropped wrong.

Why does the reverse have a mana cost?

Six mana is not nothing, but the creatures attack for 21 the next turn all by themselves.

The text is very small and hard to read because there is so much going on. It's hard to evaluate when my brain turns off at the wall of text. Let me try:

>Double strike, vigilance, battle cry

>When ~ ETBs, create three 2/3 white Human Soldier tokens with first strike.

>Whenever ~ attacks, you may sacrifice two attacking Soldiers. If you do, transform ~ at end of combat.

And the other side:

>Double strike, vigilance, battle cry

>When this creature transforms into ~, untap all creatures you control. They gain haste and battle cry UEOT. After this phase, there is an additional combat phase.

Okay, that's a bit easier to read. From a design perspective, I think this goes way overboard with the keywords. The tokens and triggered ability on the back don't need keywords. I'd also suggest having only two keywords natively on each side, maybe first strike and vigilance on the front vs first strike and battle cry on the back. That emphasizes the color change better too

The size of the tokens are weird. Soldiers are almost exclusively 1/1s. Creating three 2/3s is probably a 6 mana sorcery on its own. Also damn, I just noticed the size on the back. That's Eldrazi sized. I'd imagine something like 3/3 or 4/4 on the front and 5/5 or 6/6 at most on the back

One: I did not mean to have 2 spreate colors on both sides it was all stupposed to be boros colors.

2nd: Now that i think about it yes the keywords are a bit overboard in the percpection true.