Spider Wars, Chapter 2: Farewell Spider-Man - S5-E13
Character mistake: When Stan Lee is asking Spider-Man what he plans to do after saving all of reality, he responds by saying to find the real Mary Jane. Moments later in the final scene, Madame Web tells Spider-Man that she is taking him to find the real Mary Jane, which elicits an incredulous response from Spider-Man, as if he didn't know that was already the plan.
Answer: There are several substances in canon and non-canon that are resistant to lightsabers. Beskar, also known as Mandalorian iron or Mandalorian steel was used to make armor and weapons by the Mandalorian people. Cortosis was an ore that, when heavily refined, stopped lightsaber blades and blaster bolts. Phrik was another metal, used in Darth Sidious' lightsabers and the electrostaffs used by Grievous' robot guards. Neuranium was a very, very dense and heavy metal that was partially resistant to lightsabers, but was more often used to shield from scanners. The species orbalisk and vonduun crab had carapaces that could withstand the blow of a lightsaber.
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