A massive D&D loot table rewrote my entire campaign

The world as they knew it could be ending. Months ago, a blinding beam of light shot up into the heavens from the east, darkening the skies and unleashing all sorts of undead and monstrosities upon the land of Uta. What had the Demon Lord Shozai done? As the party ventured east with a risky plan to destroy what they called “The Anomaly,” they laid waste to a foundry where imperial Warforged were manufactured using the Druid Belric’s lightning magic. But as they rested in the forests nearby, a behemoth robot as tall as the trees assaulted the party, spewing molten metal and blasting them with a massive beam of energy from its chest.