I know the title sounds a bit weird but thats what i remember. I watched this as a kid, which was probably before or around 1990. Back then, i was pretty confused/scared by that scene. There was some kind of social event and then there was that weird alien/monster with kind of a proboscis/trunk. I believe it was considered friendly at first, but then (for some reason) mutated into a not-so friendly thing. Panic broke lose and in defense, someone cut part of the proboscis but it immediately grew back. Some man was hiding under a table and when he was trying to look what was going on, the "monster" tramped down his head but somehow in a funny way (i believe there was no blood/gore involved).
I finally found it myself.
It was created in 1981 by two countries that no longer exist in the geo-political sense, namely Yugoslavia and Czechoslovakia. Two versions of the film were made, the Yugoslavian title was 'Gosti iz galaksije' (which translates as 'Visitors From The Galaxy") and the Czech version was called 'Monstrum z galaxie Arkana' (which can be translated into 'Monster from the Galaxy Arcana').
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