@annfran
ya, it looks like a doll for me. But there are several probabilities:
1) It's a doll, the whole spectacle is for royals to be sure that princess is dead, and she can return to Arcus. While that make perfect sense, i think it's rather unlikely, since her being a small princess is entire premise of the series.
2) She is real, but in a pinch, before her execution, arcus mages would come out and slaughter culprits. That way they would gain a way to contact with the princess as someone who saved her life, and also no witnesses left that know that arcus is involved. Well, except young ice prince who knew that she was constrained by magic tool, but whatever.
3) She is real, and will just kill the attacker the moment he would try to execute her. Or evade, no matter. Spectacle just to show that culprit is not an Arcus.
4) It's a doll, and doll will get executed. And after the whole thing, in the middle of emperor grief, she will show herself, and explain that it was a bodydouble that was created by her magic.