The Battle of Meridian Plains - S1.E23

Cedric blocks the village’s water source, in the hopes that thirsty Meridianites will break down and reveal the location of the rebels’ secret hideout. There’s fresh water in a nearby lake but it’s inhabited by an elusive creature called the Kaithim, which the Guardians have to battle. But Cedric discovers the entrance to the Infinite City, just before Vathek is able to seal his comrades inside. Aldarn, separated from Caleb and with limited food before the City is inevitably overtaken, makes a tactical decision to charge the Castle. Caleb and the Guardians join the premature attack but the uprising fails and many rebels, including Aldarn and Caleb’s father, are thrown in Phobos’s dungeons