Hard to see it in this art, (took me three times to finally find realize what happened) but Orlov's confidence was well warranted as he could have handled the Boss Giants, but when the super sized boss giant stepped up, tossing one of the other giants aside, it shocked the hell out of him. Orlov never stood a chance against the big boss.
Yeah, I came to these comments just to point out how much clearer this fact was in the novel.
The boss giant is supposed to be *several* times the size of the others, and the art could've made that a lot more visually obvious. I expected to see zoomed out shots, it was supposed to be like 20 regular giants bashing the barrier and then one giga-giant that came out of the portal after they flailed about for a bit. The artist really should've done camera shots from sky level, probably about 200 meters away, to showcase the real size of the giants. Instead it turned out like... this. Sigh. The art itself is beautiful but the artist is so bad at communicating through art.