Take part in the Admiral's tea party on the TAIGA level.

Towards the end of the Taiga level you will need to power a lift inside a small factory. Once you have done this and used the lift, you will enter the humble abode of a character called 'The Admiral'. For this achievement you need to wait and listen to his dialogue and when he offers, take a seat at his table and join in the tea party. The achievement will unlock after the entire party has played out.