Nearly a tie: Greenland and Oceania differ by barely -75%% in area — about 2,154,754 km² km² against 8,600,000 km² km².
The old Mercator map treated both about equally (11.8× vs 1× inflation), so at least their relative sizes were preserved — even if both were drawn at the wrong absolute scale.
Oceania fits 0× into Greenland.