1. How gladiators fight in the series is amazing,but when gladiators wound each other,it's really stupid and you can obviously see when the blood is still in the air after 3-5 seconds (for example, when Mycter sliced Abiron's throat in the 7th episode-Libertus of Spartacus:Vengeance or when Spartacus stabs a retiarius with his own trident (fascina) in his back) and by that, you can see how blood is oversized and how long it waves in the air.

2. What's more stupid is when you can see how blood splashes and flushes so fast out of someone's head (for example when Septimus (unknown style) killed Valerius (Secutor) with his own axe (Securis) in the 5th episode-Shadow Games of Spartacus:Blood and Sand etc.)