Complex sentence: Toth also explains that the Eldar were fighting to protect the stone, as it was they who imprisoned the daemon in the stone originally: as he puts it'as Chaos's oldest enemy, the Eldar see themselves as the only capable defence against its influence.
Split into simpler sentences: Toth also explains that the Eldar were fighting to protect the stone, as it was they who imprisoned the daemon in the stone originally. As he puts it'as Chaos's oldest enemy, the Eldar see themselves as the only capable defence against its influence.