Most people have heard of sightings of gray aliens, or reptilian or human aliens,
but it is a common misconception, specially among those who do believe in those reports (who try to make sense of it) ,
that these are the only creatures seen on these ships
In fact in 20th century there have been many different descriptions of many different types of creatures.
Most of the recorded and investigated reports have included sketch artists make drawings based on the descriptions.
Here is an interesting picture I've found and scanned, which is an artists composite of a lot of different sketches.
These are colored and polished versions of sketches (based on both the original sketches and stories)
Each of these "aliens" holds a card with the year of report and place of report.
There seems to be all kinds of wild reports.
And a lot of these look ridiculous, but non of them are any more or less credible than your avarage gray story.
sorry the print is a little bad in the first one, it's was published in an old magazine.
Each of these "aliens" is from a specific story recorded in 20th century, and non are made up by the artist.
the artist simply copied documented sketches from each of these stories.
http://free-os.t-com.hr/redmist/alien1.jpg
http://free-os.t-com.hr/redmist/alien2.jpg
some of them can be interpreted as suits, some of them as robots, and some of them might simply be different renderings of the same kind of thing (subjective impression)
But just to widen the scope of what alleged "alien encounter" actually encompasses
I don't know if these are in scale, but some of them have been reported to be taller than 3 meters, sometimes between 3 and 4 meters