Possible Clues:

• Really, really tough
• Very cruel, merciless
• Cruel and inhuman
• Harsh
• In revision, keep a tight rein on short story that's mostly barbaric
• There's a nasty sort of depression in the lab up there
• Callous
• Savage not in tribunal arranged
• On the other hand - one's left restricts right, which is cruel
• Cruel routine in Bali I overlooked