One memory that I have that fits this thread perfectly has to go to the "alien invasion" from The Legend of Zelda: Majora's Mask.
Well, I say "alien invasion" but the game never really states what they are exactly, but they are at least and most definitely not from this world. To give some background for anyone that doesn't know and doesn't care about spoilers (I mean I know the game is old but just in case because you never know
) you have to reach Romani Ranch on the first day in order to reunite with your missing horse in order to continue the main game, but a sidequest is offered to you while you are there. The sidequest is to help Romani keep out mysterious creatures that appear at the ranch yearly (the "aliens"). Once you come back to the ranch during the night of that same first day those aliens will appear and start to slowly approach the barn. While the look of these creatures is not the scariest thing ever, it's a combination of the very eerie music that plays during this event, the urgency of the situation as they just keep coming and respawning even if defeated, and the consequences that occur if you fail to keep them at bay that made this a rather memorable and above all scary moment for me as a kid.
Well, I say "alien invasion" but the game never really states what they are exactly, but they are at least and most definitely not from this world. To give some background for anyone that doesn't know and doesn't care about spoilers (I mean I know the game is old but just in case because you never know
