Finished the game after 17 hours for a no kills, no alerts Goblin difficulty playthrough with all optional tokens collected and objectives completed. Styx 1 took me marginally longer for the same playstyle at 18 hours, but I attribute that to learning the mechanics of the series. Here's how I'd compare the two games:
Things Styx 2 does better than 1:
1. The control improvements cannot be overstated: Styx 1's controls were okay for the most part, but there were design decisions that were frustrating. The following were the issues I had with Styx 1's controls, and how Styx 2 addresses them:
- Styx no longer automatically climbs up a ledge he has jumped to. In Styx 1, the player had to hold down the spacebar after jumping to a ledge to prevent Styx from climbing up automatically and risk exposing himself to overlooking guards. This control mechanic took me a while to get to grips with because in the vast majority of games, the default behavior is to not climb up a ledge automatically. Thankfully, Styx 2 fixes this and the default behavior of Styx is to just hang from a ledge he has jumped to.
- Dropping down to a lower height is no longer clunky. In Styx 1, the only reliable way to walk off the edge and drop to a ledge below was to slow walk by holding down the Shift key. The problem with this control scheme is that Styx barely moves when he slow walks, and as a result, dropping down to a lower ledge to evade a guard's field of vision was more frustrating than it needed to be. Styx 2 refines this by requiring the player to just hold down right-click to drop down below, and Styx is able to do so without slowing down.
- Styx can turn corners when he is hanging from a ledge in Styx 2. In the first game, Styx had to climb up a ledge, turn the corner and then drop down again whenever he encountered any ledge that was not a straight line. Though this change in Styx 2 is welcome, I initially thought it would make the game too easy. Thankfully, the designers took Styx's increased mobility into account, and guards are better at detecting a ledge-hanging Styx compared to the first game.
2. Use of invisibility and sacrificial clones is far less mandatory: In the first game, a no kills, no alerts run required the use of invisibility and clones as bait for a lot of optional objectives. The temptation to use these aids was strong even in parts of the main objective, especially towards the end. This problem mainly stemmed from the fact that Styx was limited in his ability to create diversions in the first game. In comparison, the sequel gives Styx a variety of tools such as thrown bottles to catch the attention of guards, needles to cause guards to get sick temporarily, and the ability to instantly swap places with a clone. The end result is that the usage of invisibility or sacrificial clones to alert and draw guards away from a choke point can be entirely avoided. Sure, certain optional objectives requires a fair bit of experimentation to pull off, but at least I didn't have to deal with the cognitive dissonance of having to alert guards with a clone in a ghost run, as it was in the first game.
3. There is more variety in the level design: Both games are cut from the same cloth when it comes to general level design principles -- large maps with an emphasis on verticality and multiple paths to the objective. The improvement in the second game is from the wider pool of level archetypes it draws from: an elven city, a coastal town, an airship, etc, each leading to a slightly different playstyle. The elven city is the most vertical of all the map types, and the coastal town features a lot of traversal via ropes. The airship has complex interiors with guards overlooking each other. This level variety in Styx 2 makes the recycled maps a bit more palatable compared to the original's recycled maps that weren't too different from one another in style.
4. The visuals are massively improved: I doubt people play stealth games to ogle at the screen, and normally the visuals hardly matter as long as they are functional. But I want to call attention to Styx 2's visuals to give credit where it's due. For a 2014 game, Styx 1 was quite an ugly game, but it was easy to justify given its budget. I'm assuming Styx 2 featured a similar budget to Styx 1, but the game looks spectacular without sacrificing any of the complexity from the 1st game. I'd have been okay with a Styx 2 that looked like the 1st game, but I was positively surprised by how the sequel ended up looking.
Things Styx 2 does not do as well as the first game:
1. Enemy AI is dumbed down: Styx 1's enemies were already not the brightest around and nor did they possess the sharpest sight or hearing in stealth games. Inexplicably, Styx 2's enemies became even more short-sighted, routinely failing to detect Styx when crouched 5 feet away in front of them. Furthermore, the enemies in the second game go through an additional alert phase before hunting down Styx compared to the first game (they go from White->Yellow->Orange in the 2nd game, whereas the 1st game used the White alert phase only for specific actions such as putting out torches. The rest of the time, the guards started at the Yellow phase). As mentioned before, the only real AI upgrade is in their detection of Styx when he is hanging from a ledge.
2. Enemy design is far too forgiving and similar to one another: The 1st game had different enemy types, each of which presented different dangers. Styx 1 had elves who could detect Styx if he was remotely near them, even when he was above or below them. There was little Styx could do to circumvent their sensing of him. There is nothing that presents the same level of challenge in the sequel. Dwarves could have filled this void with their ability to smell Styx out when he is nearby, but even their special ability is neutralized by a potion, turning them into a poor man's elves from the first game. Moreover, the 1st game had hostile Styx clones who could instantly detect Styx's presence and orcs who would instantly punish noise. Compared to these enemy types, the 2nd game has a bunch of humanoids: elves, humans, trolls, etc., but for all intents and purposes, there is no real difference in how one sneaks by any of them.
3. Relics are sorely missed: One of the best design decisions of the 1st game was in the deciphering of the locations of relics from rough hand-drawn maps. The maps were approximations at best, and required the player to pay attention to his surroundings to locate possible relic spots. Even when located, actually accessing the relics was a tense affair since the player frequently solved the accompanying puzzle while dodging patrolling guards. Instead of taking the best designed relics from the 1st game and improving upon them even further, the 2nd game completely omits them.
4. The mandatory boss fights are even worse this time around: Both games feature out-of-place mandatory encounters that would have been better left on the cutting floor. The encounters in the 1st game were jarring because ghosting through the encounters was not a viable option; killing the targets was necessary, but at least the encounters played by the prior rules: one could go invisible to reset the fight and kill just the necessary targets. In comparison, the 2nd game's mandatory encounters feature a big spectacle, but all prior stealth rules are thrown out of the window. The bosses feature no real AI to speak of, instead triggering attacks when Styx crosses a predetermined spot. Going invisible does not help, and the player is forced to essentially play through a visually pretty but scripted sequence. And adding to the frustration, saving is limited or absent during these encounters, and so not sticking to the script leads to replaying large parts of the encounter all over again.
5. The game ends abruptly: Imagine the 1st game, rip out its final level and play the credits; that would echo the bewilderment I felt on finishing the 2nd game. It comes out of nowhere, with no buildup, and it feels that the game decided to arbitrarily end at the point it does. Apart from the narrative issues this ending poses (plot threads are left dangling), the bigger issue is a gameplay one since the 2nd game does not escalate in the degree of challenge presented unlike the final level of the 1st game.
Overall, the 2nd game made some much-needed improvements to the Styx formula while also unfortunately regressing in a few areas. Since the Styx games fill the no alert no kills stealth niche that few games do, I'd say I enjoyed both games though they both suffer from different issues. For a 3rd game (hopefully the sales pick up and there is one), I'd combine the best aspects of both games: combine the enemy design and relics of the 1st game with the control improvements and freedom of play of the 2nd, with more aggressive AI than seen in either game. And leave mandatory encounters out entirely.