At C1, inversion extends beyond negative adverbs to "so/such" structures, conditional inversion, and locative inversion for literary effect.
Negative adverbs (review)
Never have I seen / Rarely does she complain / Hardly had I sat down...
So/Such + adjective
So beautiful was the view that we stayed for hours.
Conditional inversion
Had I known / Were I to leave / Should you need...
So / Such inversion
Emphasising degree or extent
So + adjective/adverb + aux + subject + verb that + clause ✓
So + adjective
So tired was she that she fell asleep immediately.
So + adverb
So quickly did he run that we couldn't catch him.
Such + noun phrase
Such was the storm that all flights were cancelled.
Such + noun
Such confusion was there that nobody knew what to do.
Conditional inversion (review)
Had + subject + PP
Had I known earlier, I would have come.
Were + subject + to
Were she to apply, she'd certainly be hired.
Should + subject + base
Should you require assistance, please ask.
Were it not for...
Were it not for his help, we would have failed.
Had it not been for...
Had it not been for the weather, we would have won.
Locative inversion (literary)
Place expression at start triggers inversion of verb + subject
Direction
Down the hill ran the children.
Place
In the corner stood a large grandfather clock.
Position
On the wall hung a portrait of the king.
Locative inversion is mostly literary or descriptive. It cannot be used with all verbs — typically with verbs of position (stand, sit, lie, hang) or motion (run, come, appear).
Inversion with "only"
Only after
Only after the meeting did I realise the mistake.
Only when
Only when she left did he understand his feelings.
Only by
Only by working hard will you succeed.
Only then
Only then did I see the truth.
Just "only" by itself doesn't trigger inversion — needs to be part of a longer phrase (only by / only when / only after / only then).