The only thing I can add in support to the Half Life games, that hasn't been said by others, is pacing.
Seriously, It was almost unheard of for an action orientated FPS to have pacing back then, let alone do it well, and even now most FPSs completely forget to set a good pace.
Most modern military shooters, and much of the FPS genre, have this issue of cramming as much action as possible into the game, meaning at the end of the relatively short 3-5 hour campaign you feel burnt out. There is no escalation in the conflict, there is not contrast to the action... there is no variation. They are fast and loud and incessant.
HL2, for its time, did pacing wonderfully. You game escalates from being pursued by corrupt authorities. with peaks and lulls in the action and climaxes at an impressive aerial battle, then after a brief sequence for exposition enters a horror themed environment where you are scrounging for ammunition and fending off hordes of undead husks (very memorable segment, a little short, but brilliantly done). The final moments of this section puts most attempts at zombie horde games to shame.
After this you end up on a journey across a vast stretch of road on approach to a prison facility. While the driving mechanics are awkwardly dated, the pacing of this sequence is superb. Periodic firefights at small settlements (some which can be avoided, but generally it's good to stop and resupply) and regularly being accosted by underground dwelling aliens (who are also aggressive towards other humanoid combatants leading to intense 3 way conflicts), makes the relatively long segment pass fluidly. There are a few intense "boss" fights that make the peak moments pretty memorable. The conclusion of this segment foreshadows the final segment of the game, with you and a band of rebels hold off against a Combine strike team at a lighthouse.
The next major segment of the game puts you on the attack, completely changing the flow of gameplay. Enemies aren't dropping in and harassing you as they did before. Instead you attack entrenched positions that have to adjust to your actions as you catch them unawares. This leads to the next horror themed sequence though the horror is more subdued as the scope and purpose of the alien incursion becomes apparent.
The second last segment of the game ramps of the combat to 11 as you battle your way through a city that is now undergoing an uprising. Rebels and Military combat each other, with alien monstrosities create havoc all around.
Finally the last segment dials the action back but empowers you, becoming a death dealing machine.
And this is just HL2. Episode 1 and 2 have completely different pacing structures that improve on HL2s forumla, though are significantly shorter over all. Each sequence of the game flows organically into the next, so much so you hardly notice the transition but feel the change in other ways. Lulls and peaks of the game make every sequence memorable, contrasting intense firefights with eerie exploration and tension building.
HL2 is a masterpiece when it comes to pacing, an art that truly makes a good game great, but if ignored can make any game shit or average regardless of technical achievements and ambitions. Of all the things modern shooters borrowed from HL2, pacing is the one thing not acknowledged or adapted despite it being exemplary (for games in general, not just FPSs). All the flashy gimmicks that HL2 pioneered mean nothing but that, gimmicky, without the expertly crafted sequences to showcase them.
This is why HL2 feels so good, but why people find it hard to articulate why without sounding hypocritical. Its not all the physics, which are done better now, or the narrative, which there are more interesting of now, or the characters, which were adequate vehicles for the narrative but nothing special, or fundamental gameplay, which most modern games trump handedly.
Its the cohesion... how all of these things, no matter how dated, hold together as one piece. The pacing is the adhesive that ties all these things together to form a memorable experience.
Valve are the grandmasters at this. More narrative heavy games still fail on such a simple concept, but valve nail it EVERY time... even in games with roughly no narrative like Left 4 Dead.
Seriously, It was almost unheard of for an action orientated FPS to have pacing back then, let alone do it well, and even now most FPSs completely forget to set a good pace.
Most modern military shooters, and much of the FPS genre, have this issue of cramming as much action as possible into the game, meaning at the end of the relatively short 3-5 hour campaign you feel burnt out. There is no escalation in the conflict, there is not contrast to the action... there is no variation. They are fast and loud and incessant.
HL2, for its time, did pacing wonderfully. You game escalates from being pursued by corrupt authorities. with peaks and lulls in the action and climaxes at an impressive aerial battle, then after a brief sequence for exposition enters a horror themed environment where you are scrounging for ammunition and fending off hordes of undead husks (very memorable segment, a little short, but brilliantly done). The final moments of this section puts most attempts at zombie horde games to shame.
After this you end up on a journey across a vast stretch of road on approach to a prison facility. While the driving mechanics are awkwardly dated, the pacing of this sequence is superb. Periodic firefights at small settlements (some which can be avoided, but generally it's good to stop and resupply) and regularly being accosted by underground dwelling aliens (who are also aggressive towards other humanoid combatants leading to intense 3 way conflicts), makes the relatively long segment pass fluidly. There are a few intense "boss" fights that make the peak moments pretty memorable. The conclusion of this segment foreshadows the final segment of the game, with you and a band of rebels hold off against a Combine strike team at a lighthouse.
The next major segment of the game puts you on the attack, completely changing the flow of gameplay. Enemies aren't dropping in and harassing you as they did before. Instead you attack entrenched positions that have to adjust to your actions as you catch them unawares. This leads to the next horror themed sequence though the horror is more subdued as the scope and purpose of the alien incursion becomes apparent.
The second last segment of the game ramps of the combat to 11 as you battle your way through a city that is now undergoing an uprising. Rebels and Military combat each other, with alien monstrosities create havoc all around.
Finally the last segment dials the action back but empowers you, becoming a death dealing machine.
And this is just HL2. Episode 1 and 2 have completely different pacing structures that improve on HL2s forumla, though are significantly shorter over all. Each sequence of the game flows organically into the next, so much so you hardly notice the transition but feel the change in other ways. Lulls and peaks of the game make every sequence memorable, contrasting intense firefights with eerie exploration and tension building.
HL2 is a masterpiece when it comes to pacing, an art that truly makes a good game great, but if ignored can make any game shit or average regardless of technical achievements and ambitions. Of all the things modern shooters borrowed from HL2, pacing is the one thing not acknowledged or adapted despite it being exemplary (for games in general, not just FPSs). All the flashy gimmicks that HL2 pioneered mean nothing but that, gimmicky, without the expertly crafted sequences to showcase them.
This is why HL2 feels so good, but why people find it hard to articulate why without sounding hypocritical. Its not all the physics, which are done better now, or the narrative, which there are more interesting of now, or the characters, which were adequate vehicles for the narrative but nothing special, or fundamental gameplay, which most modern games trump handedly.
Its the cohesion... how all of these things, no matter how dated, hold together as one piece. The pacing is the adhesive that ties all these things together to form a memorable experience.
Valve are the grandmasters at this. More narrative heavy games still fail on such a simple concept, but valve nail it EVERY time... even in games with roughly no narrative like Left 4 Dead.