re: Favorite FPS of all time and why?
For me it's between..
Resistance: Fall of Man. A PS3 launch title that has long since been forgotten. It was developed by Insomniac who are better known for their work on the old Spyro games, Ratchet & Clank, and most recently Spider-Man. It was a very arcade-like shooter. The story was an alternate WWII where an alien species invaded earth and while it might sound like a boring cliché story it was actually very well written and fleshed out. Bonus points for being able to play through the campaign in 2 player couch co-op. The multiplayer was where it was at though. I never considered myself a fan of shooters but this game got me hooked. With large maps (which would be cut up into smaller sections for 8-player game modes like death match), a vast arsenal of exotic and unique weapons (something Insomniac was always known for), tons of game modes (classics like TDM and CTF, but also brand new modes like Breach and Meltdown), and an unprecedented (at the time) 40 player MP experience, this was about the only game I played until 2008 when Resistance 2 launched.
Unfortunately, while R2 improved and expanded in some areas (graphics, 60 player MP, 8 player unique co-op mode), Insomniac tried to get in on the COD hype train and stripped a lot of things that made Resistance unique to appeal more to the "casual" COD crowd. Resistance 2 was still a very good game but it didn't have that same magic. And then came Resistance 3.. For some reason, even after all the feedback from loyal and passionate fans, Insomniac doubled down on their decision to make a more COD-like shooter. The result was a third entry that bombed commercially. I didn't even bother buying it at a massive discount after I had tried the beta months prior, it wasn't at all the game that started my love for the franchise. In 2019 few people remember Resistance, servers have been long since shut down, nobody talks about it and there doesn't seem to be any desire from fans or developers to revive it. And as much as I loved RFOM, if they're not going to stay true to what made it a unique game in the first place but instead insist on being a weak sci-fi COD knock off, it can stay dead.
Call of Duty: Black Ops 3: probably an unpopular opinion. I always preferred the Treyarch CODs, I never really got into MW (see above, I was hooked on RFOM at the time) and MW2 wasn't fun at all to me even though most people praise it as being the best COD ever. To me, Black Ops 3 was as close to the perfect COD experience as you could get. I've never cared for the campaign in COD so I'll disregard that aspect of the game right from the start. I'm a huge fan of the zombies mode ever since I first played it on World At War, and Black Ops 3 provides the best zombies experience hands down. The only downside is you need four $15 dlc packs, a standalone $5 map and another $30 dlc pack to enjoy all the content, yeah that's a lot of premium dlc for one game. If you do have all the dlc though, you get a mix of massive, quest and story driven zombie maps specifically made for BO3. Tons of things to do in those maps, on top of trying to survive endless waves of the undead. And you also get about 5 or 6 of the classic zombie maps that are remade to look beautiful, where the only objective is basically to survive as long as you can. Whichever style of zombies you prefer, BO3 has you covered.
Multiplayer is where I spend the majority of my time. BO3 is one of the three COD games that had wall running and jetpacks. While most people seemed to prefer boots on the ground, I thought the jetpack COD gameplay was vastly superior in every way. I could play BO3 MP for hours on end with my friends. Tons of challenges to work towards, dozens of camos to unlock for every gun, outfits to unlock for all the characters, there was always something to do. Multiplayer was centered around the new specialists, who were pretty much based off of Overwatch. Gain score to fill up your meter and when it's full you can use your specialist ability or weapon. None of the specialists really felt overpowered or cheap to play against so I didn't have a problem with them here. The only real negative to BO3's multiplayer was the goddamn loot boxes. Never have I seen a more consumer unfriendly way of going about them than I did here. They would periodically release new weapons, none of which were particularly good or didn't have a base-game equivalent that played almost the same, but you had to rely on RNG to get these weapons which means some people would never even touch most of these weapons. I guess they were kind enough to occasionally give out "Triple Played contracts" which would guarantee you a new weapon, so even the most unlucky people would get at least one weapon. I had a ton of luck with the loot boxes, ending up with owning every single weapon in the game without spending money, which is probably one of the reasons I look back so fondly on this game.
I guess with Black Ops 3, if you had the full package and full experience like I did (own all zombie maps, get lucky with loot boxes and own all dlc weapons) it was a fantastic game. I actually went back a few days ago to play a couple games and it was still a very fun game. If you didn't have or want the dlc maps, and you kept getting screwed over with loot boxes I imagine your experience with this game would greatly differ from mine. I'll always look back on it as a great game with very fun and addictive gameplay. Even after I got COD Infinite Warfare and COD WWII (the two subsequent releases in the franchise) I still went back to BO3 because those games weren't able to draw me in like BO3 did. I only stopped playing late last year when Black Ops 4 released. I hadn't played a shooter for 2 years straight since the days of Resistance.
Tl: Dr - Resistance Fall of Man and COD Black Ops 3, two very different FPS games that I played for 2 years straight, 10 years apart.