i got the 1st game together with my ps4 back then. i remember it was good fun but ultimately lacking something for me to go back to it. it looked sweet and being a big fan of the world i enjoyed strolling through it as a powerful dude that can battle 20 orcs at a time but not be invincible. i found only certain orcs to be a real challenge though. i don't remember exactly what the traits were, because it's a long time and quite a few games ago for me, but i think it was an invulnerability to certain attacks that made a few orcs stick out to be an actual challenge, while the others were rather easy.
some things definitely need to be fleshed out, so you have a reason to come back to the game even after you beat it. the easiest way and one i really prefer is a simple additional difficulty level you unlock after the 1st playthrough. and can be a bit more creative than just "more enemy damage and armour", maybe a maximum number of player deaths per playthrough or something similar. make it hard and challenging and simply don't attach any trophy or achievement to it so people can still get 100% if they choose to not play this mode. god of war 3's hardest difficulty didn't have a trophy either, but there are still players like me who enjoy these challenges even without digital bling :)
@vid-lock: or have a positive impact on the gameplay, like the blast shards in infamous. because most collectibles in most games are simply there to prolong the playtime, by either making it have no purpose at all, besides reaching that 100% completion (hello AC) or netting you a trophy/achievement, or give you some mostly not needed background info in form of a letter (audio diaries in bioshock were pretty cool though). If you would know that the collectibles actually strengthen your character or unlock something later on that would be really cool to have there would be a much different motivation to go look for them.
@fetcher: in dark souls you can play online and make sure never get invaded by just not reviving yourself. it's a perfect system. if you want to summon others then of course you have to make yourself vulnerable to invaders. that's why i do the 1st playthroughs of these games solo, so nothing can distract me from my personal experience.
@PSYCHOV3N0M: yeah, i'd love that. too many open-world games out there nowadays. linear games always were the better quality games in my opinion, since they usually don't lose focus and keep everything tight. the greatest open-world games i played still couldn't match the experience of e.g. a dead space or bioshock or last of us.
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