Perfect Dark is a great game! although I never really tried to complete the single player campaign, I love the bot mode the best. Where I can hone my skills in deathmatch mode without needing another human player to play with. like you need in order to play multiplayer in 007 Goldeneye
I got sick of 007 Goldeneye so I no longer have that game in my collection. I got "Perfect Dark" a while ago.
But many need to know that Perfect Dark, requires the red colored 8mb expansion chip. In order to play the campaign but your allowed from my knowledge to play the bots "in the combat simulator section" even without the 8mb upgrade RAM computer chip
(for those who don't have the red upgrade it's easy to install and well worth obtaining it in my opinion)
This computer chip is vary easy to install and the best part you don't need to take your Nintendo 64 apart to install it, just need to open the expansion bay slot on the exterior of the console, than pop the black colored chip out and gently insert the new red colored computer chip.
I think you can use a butter/table knife to do this but I never done it myself since I purchased the N64 with the Expansion 8mb chip already in mine.
pricey on Amazon now but you can also buy a Nintendo 64 with one already installed
https://www.amazon.com/Nintendo-64-Expansion-Pak/dp/B00000INR2