Dieter: I moved a couple of two-headed dragons to where they belong, but now there is duplicate material on this page. However, it is late, and somebody else is invited to WME this page.
A "two-headed dragon" is a position where two eyes that are at first sight false eyes are nevertheless enough for living. To get this position, the group has to be a ring around some living group of an opponent, as in this diagram. Because the eyes are connected to each other in both directions, White cannot play at either of them first, and thus they function as real eyes, even though they have all the looks of false ones. In actual play, these positions are extremely rare but not non-existent.
Note that the definition ...
... covers this "beast".
Hmm... really?
Not all chains reach the same two virtual eyes. For a full discussion see EyeDefinitionDiscussion.
Matt Noonan: Constructive proofs are nice. :) Also, see Instant Eye Tester for a position in which Black has two living eyes, but all the diagonal points of those eyes are occupied by White.
And how about this one? A baby dragon? ;-)
No, I would consider these two normal eyes, not two 'seemingly false' eyes. The 'missing point' is not under white's control. -- Andre Engels
'Missing point'? Anyway, I just brought it up because I think these eyes are as false as those in the first diagram.
aLegendWai: I feel it is a baby dragon. The point looks like a false eye. Anyway, differen people have different feelings. :P
See also the pages in the Eyes Collection.