Intelligent Deathclaws

From the introduction: Like all good things, Intelligent Deathclaws are a type of Deathclaw that were experimented on by the Enclave in 2235. Exposing captured Deathclaws to FEV boosted their intelligence and gave them the ability to talk, among other perks. It was the Enclave’s hope that these mutated Deathclaws would be intelligent enough to obey orders without question. Naturally, that didn’t go so well.