QuoteL plays a Sauna.
L draws a card.
L plays a Sauna.
L draws a card.
L plays an Apothecary.
L shuffles their deck.
L draws a card.
L reveals a Gold, a Province, an Apothecary and a Sauna.
L topdecks a Gold, a Province, an Apothecary and a Sauna.
L plays an Apothecary.
L draws a card.
L reveals a Silver, a Gold, an Apothecary and a Sauna.
L topdecks a Silver, a Gold, an Apothecary and a Sauna.
L plays 3 Silvers.
L trashes 2 Provinces.
L buys and gains a Duchy.
L draws 5 cards.
Yes I know this probably counts under "trashing valuable cards" - I think the AI is mistaking the optional trashing on Sauna for obligatory.
A similar thing just happened to me:
Game#2058068
Turn 14 - Lord Rattington
L plays a Sauna.
L draws a card.
L plays a Sauna.
L draws a card.
L plays a Copper and a Silver.
L trashes 2 Provinces.
L buys and gains a Silver.
L draws 5 cards.
Whoops, pretty much insta-loss.