It may be an "insult" or a label for a specific type of ineffective player or user in online communities.
The plural genitive form of "mosquito" in Czech. Potential Contexts
Knowing if it was in a specific book, game, or online forum would help in identifying if this refers to a specific fictional character or a regional joke.
It could be a humorous nickname for a low-level character or NPC in a game where "mosquitoes" are a common enemy (such as Grounded or various fantasy RPGs).
A common Czech adjective used to describe lack of intelligence or a senseless action.
One who smashes or destroys things. In this context, it implies someone who kills insects with physical force rather than technical tools.
It might describe a person who spends a lot of effort trying to physically swat mosquitoes with their hands in a "stupid" or clumsy way. Comparison to Similar Terms
: The standard Czech term for a flyswatter. "Lapač hmyzu" : An insect trap or bug zapper.