Since Spartacus: Gods of the Arena can’t end on a cliffhanger because it leads into the first season, I guess there’s a structural reason why “The Bitter End” was the worst episode of the miniseries. Personally, the fights have never been that interesting; heads get cut off, limbs are severed, blood flies everywhere, but it’s all the same. What makes Spartacus interesting is the plot, and the episode dispenses with that quickly, the main battle between Quintus and Tulius resolved in the first half of the episode.
There are flecks of Spartacus we like–Solonius turning on Quintus, Gannicus winning his freedom–but overall, second half is pretty much a snoozefest. There’s little plot or intrigue and most of it is a huge, silly fight which ends with Gannicus winning and a jaw literally ripped apart. What’s disappointing about the fight is that the writers never slow the action in favor of real tension which could have made us believe or even consider that something horrible may happen. The miniseries ends with Quintus delivering a grand speech about how high he’ll rise, before the writers take out a 100-foot tall, blinking neon sign declaring, “This is IRONIC,” with the shot of Quintus and Lucretia dead.