Warning: Contains spoilers for primarily The Chains of Harrow, but also The War Within and The Sacrifice quests in Warframe. I highly suggest playing through those three quests before reading this.
After Rell is released by the Tenno, a lone figure enters the now-dark temple. Palladino is paying a final tribute to her order’s most honored figure. But it seems Rell isn’t quite done. He leaves behind a legacy — someone else who can pick up the mantle and train the Tenno in his stead.