if you make it so theres a constant struggle that keeps the player fighting to survive then it becomes fun but if theres too much time where you just stand around and do whatever you want you’ll lose the players attention
think of the gameplay like a graph
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if the player isn’t active he’s not having fun and you get a flat part on the graph
the trick is to get the player excited with a good hook like when you watch a good action movie its starts off with some crazy action scene you have no idea whats going on but your watching the movie cause its got your attention with that hook then theres always those ups and downs in the graph in this case the movie would have the boring scenes where characters talk(this is the down part) then all of a sudden bam theres people shooting and blood everywhere and those are the up parts of the graph
every good movie, game, book follows that graph they get you with that hook then theres a few small ups and downs and we all heard of the grand finale well that part is just a big spike at the end of the graph thats the part that seals the deal and makes people remember the game,movie or book
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a survival game could work but you need to find the right balance keeping the player entertained and having fun
alot of games have bosses at the end of each level to keep the player looking forward to something or they have a cutscene for the player to watch between levels
if your going with a free roam game then you need a story for the player to look forward to
any game can be turned into a good game its just a matter of good game design