The Philosopher's Stone Stops Being a Treasure Hunt Here
SPOILER!The building eventually disappears. The information the brothers learn there does not.
Episodes 18–19 · Ed and Al find the Fifth Laboratory
Prisoners are the supply chain
Slicer Brothers · Barry the Chopper
Lab 5 guardians · Ed's mirror fight
Serial killer · armor-bound soul
Episodes 21–22 · make the Stone or watch people die
The cost is visible this time
Lust and Envy can arrange the conditions, but Ed must transmute
Greed · chimeras · Tucker
The rogue Homunculus is already a containment problem
A State Alchemist kept useful after becoming a monster
Episodes 22–25
The investigation gets bigger than Ed and Al