Achron

Developer:  Hazardous Software

Rating:  4/5

Bottom Line:  Achron is a groundbreaking RTS with unique and interesting gameplay mechanics and an extensive campaign, but the lack of modern RTS conveniences hampers the experience to a significant degree.  I can highly recommend this as an experiment, and as an experience, but not as a finished, polished game worth the price.

Introduction and Conceptual Overview

Back in the mid ’90s, a friend of mine and I had a number of conversations about game design.  A lot of ideas got thrown around, but I had two that I thought were particularly good.  The first was for an RTS-style game where you recruited troops, but didn’t actually directly control them.  They would roam around, controlled by their own AI tropisms, and find things to accomplish, gaining skill all the while.

Something very similar to what I had envisioned was produced a couple of years later:  Majesty.

My second idea was for an RTS that involved time travel.  The player would be able to call reinforcements to them from further up the timeline.  This would provide a quick burst of fresh troops, but a matching amount of troops would have to be built and positioned properly in the future in order to jump back.  Failure to do so would cause “paradox storms”, which would inflict increasing amounts of damage to the player based on the magnitude of the temporal imbalance.  I particularly liked this idea because (I thought) it would provide interesting counters to rush strategies — you could focus on economy, block an initial rush with up-time reinforcements, and end up with a substantial production edge over a more militaristic player.

Although it doesn’t map exactly onto my simplistic original idea, an RTS game based around time travel mechanics has just been released:  Achron.  And it’s a fascinating, if flawed, game.

In Achron, you, as the leader of your forces, sit outside the timestream.  Through the “timeline” user interface feature (easily the best-designed portion of the UI) you have access to time periods from about 4 minutes prior to the game’s “present” to 1 minute in the future.  It’s very much like a minimap, but for time rather than space.  At any given time you can click at a point on the timeline and the game will instantly snap to what was happening at that time.  But that’s certainly not all.  You can also issue commands to units in the past or future, at the cost of “chronoenergy”, a resource that is achronal (that is, uncoupled to in-game causality) and which regenerates at a fixed rate in real time.

The upshot is that you can not only observe the past, you can change it.  If you fight a battle and lose, you could jump to a period of time before the battle began and redeploy your forces, or even disengage and move elsewhere.  In multiplayer games, there could be up to 3 other players also manipulating the timestream in this way, so you can see that it could get very complicated very quickly.  If I jump back a minute and tell my forces to take the left fork rather than the right fork, you might jump back a minute and a half and redeploy your forces to again cut me off.  As long as the chronoenergy holds out, there’s no hard limits to what can be done.

The game handles the results of this time manipulation through an ingenious, if imperfect, mechanism:  time waves.  The game cannot instantly propagate changes you make throughout the entire timeframe of the game in real time; that would be computationally prohibitive.  Instead the game uses periodic “waves” of causality that propagate up through the timestream at a fixed rate (about 3 times the normal rate that time passes).  As a time wave advances up the timeline, the game modifies history according to any changes that have been put in play.

This leads to interesting effects when a time wave catches up to whenever you happen to be observing on the timeline — if someone has made a change to the past, your units may move, shift position, or disappear as a result of the changes.  It can be very disconcerting to have the rug yanked out from under you and your forces defeated somewhere in the past.

The limit to all this temporal manipulation is the fact that the farther back in time you go, the more chronoenergy you use to issue commands.  At some point in the past, the energy required to issue a command is greater than the maximum chronoenergy you can accumulate.  That point is the threshold of the “unplayable past”.  Points previous to this may be visible, but can’t be further changed.

But the time travel mechanic isn’t limited to issuing orders in the past and future.  It’s also possible (with the correct technology) to “chronoport” units through time.  Send a squad of tanks three minutes into the past, and you now have additional forces earlier in the game’s timeline.

Time travel inevitably leads to time travel paradoxes, and the game’s time wave mechanic provides a means, albeit imperfect, to resolve them.  The “grandfather paradox”, where a unit travels back in time to before it was created and kills the building that produced it, is pretty trivial to set up in Achron.  The way this plays out in the game is that successive time waves alternate between states of the paradox.  On one pass, the building will be present with no unit.  On the next, the unit will be present with no building.  Whichever state obtains when the event falls off the “past end” of the timeline is locked in as the permanent state.  As you can no doubt imagine, all sorts of weird abuses are possible with these temporal tools.

It’s worth pausing here a moment to, well, bask in the glow of the amazing time travel mechanics Achron implements.  Mostly because when I get into the details of how the game is constructed, that glow will fade quickly.  So let’s take a moment to acknowledge the genius design and tremendous work behind Achron‘s temporal mechanics….

Ready?  OK, on with the review.

Single-Player

The single-player campaign is extensive, consisting of four parts:  one for each race and one final campaign (that I haven’t gotten to yet).  Most of the early levels are devoted to teaching you basic RTS skills, followed by the temporal mechanics.  There is a fairly detailed, serviceable backstory, involving a coordinated alien assault against human colonies.  You are alternately playing either one of the human commanders or his suspiciously-powerful AI, while political infighting, treachery, alien slavery, and the sordid history of the human military’s relationship with AI entities provides the dramatic motivation.

The missions move pretty slowly if you’re used to a standard RTS like Starcraft 2.  In addition, the missions are a bit different than RTS standard.  For one thing, they’re a lot more finicky; you must almost always keep certain units alive, which can be quite difficult at times.  This isn’t as bad as it could be, however, as if they die you can simply jump back in time and change history to ensure they survive.  If you fail repeatedly, however, the escalating cost in chronoenergy can make it more and more difficult to retry as you are forced farther back on the timeline, and losing due to an event receding into the unplayable past after multiple failures can be incredibly frustrating.

Multiplayer and Skirmish

I’ve played very little in the way of multiplayer — a couple of skirmish games.  But I’ve seen enough to show me that multiplayer Achron is a different beast than the single-player campaign.  First of all, you’re always playing against an opponent who can counter your temporal maneuvering, which is very fun.  Several times I started firing on an enemy unit only to watch a time wave go by and the enemy unit disappear, presumably rerouted at an earlier point.  Several interesting strategies are possible in Achron that are not possible in other RTS games, such as a “race-switch”:  since your faction choice is selected in-game, it’s possible to jump back in time and select a different starting race, potentially throwing off early scouting by your opponent.

There are three races in Achron, roughly analogous to the three races of Starcraft.  The humans have the best firepower, the Vecgir have integrated teleportation in their vehicles, and the Grekim have an inherent chronoportation ability (albeit one that costs so much that it’s not as useful as it sounds at first).  Their tech trees are somewhat different, but the units each faction has, when boiled down to essentials, are very similar.

Unfortunately, the victory conditions can be somewhat of a trial.  I don’t know if it’s the only way to win in a multiplayer game, but in my skirmishes you had to completely eliminate the enemy forces and production facilities at the earliest point on the timeline.  When playing the computer, this meant that I had to kill everything I could find, and then sit around for five minutes while the timeline scrolled those deaths off into the past.  I started messing around with chronoportation to kill time, until finally receiving the “game won!” notification.  A human opponent would likely concede, but a griefer could tie you up for quite a bit longer in Achron than in something like Starcraft 2.

The AI itself doesn’t seem too strong, even for someone of my modest skills, but I’m not sure I’m playing at it’s highest level.

Production Values

This is where Achron‘s conceptual brilliance most obviously yields to muddled execution.  Sound in the game is generally good — the effects are fine, the voice acting for some characters is a bit over-the-top but not annoyingly so, and the music is quite nice.  Unfortunately, the same cannot be said for the graphics.  Units are rather generic and hard to tell apart, animation is sparse at best leading to a poor sense of responsiveness from the controls, and the cutscenes, although they do their job in terms of communicating the setting and backstory, look really crude, even for an indie game.  Maps are bland and drab, and do nothing in terms of establishing a sense of place.  A complete reskin would be a great fan project, and would do wonders to improve the game.

This is, of course, an indie game, but one with a split personality.  Achron costs $30, well above the standard amount for an indie title.  Even though you get two game keys for this price, it’s still steep for an indie impulse purchase.  On the other hand, it’s got a lot of content and obviously aspires to cover all the bases of a full-fledged, major-release RTS.  By indie standards the production values are acceptable, but the price is high.  By the standards of major releases, the price is great but the production values are really weak.  Trying to straddle this line has resulted in a game that doesn’t really fit in either world, unfortunately.

One overall mitigating factor I should mention is that the game is designed with moddability in mind.  Undoubtedly, over time, mods will be released to tune up the maps and models and give Achron the graphical polish it deserves.

Mechanics

Compared to a AAA+ title like Starcraft 2, it would be unrealistic to expect that Achron would be able to compete on fluidity of mechanics.  But even given a lower level of expectation, there are a number of mechanical and interface features that Achron implements really badly.

Pathfinding and unit movement is deficient on a number of levels.  Although I believe the pathfinding algorithm is close to where it needs to be, there are still some spectacular failures from time to time.  Exacerbating the problem is the fact that units won’t shift to let allies through their position, which causes huge pile-ups that have to be resolved manually — potentially at a high cost in chronoenergy (hint: play Vecgir.  Built-in teleportation means you can avoid most of these problems).  Most maps don’t have very many obstacles, and teleportation is used by two of the three races as a key movement mechanic.  Both of these factors help, but wrestling individual units to get them to walk across the map is the antithesis of fun.

The other major mechanical problem is in the implementation of group command and organization in different time periods.  The game assumes that when you issue an order to a unit in the past, that you mean to add that order to the unit’s existing queue, leaving later orders intact.  In a few cases this might be correct — if you jump back and tell your unit to cloak, for instance, you may still want it to move, fight, etc. like you will order it to later in the timeline.  But in a large — very large — subset of cases, you want to completely override previous orders (such as when you decide that attack-moving into your enemy’s base wasn’t such a good idea after all).  In such cases, you either have to issue a “cancel orders” command before issuing the new command, or watch your units follow your new order for a while only to reverse and start heading back the other way when the timeline catches up to the original order.

Achron‘s system is flexible, yes.  It covers all situations, but it’s clunky and adds annoying micromanagement to what should be the most fun part of the game.  Similarly, chronoportation has a number of limitations that make it hard to use properly.  Normally giving a command to a group leader will cause subordinate units to follow along.  This is not true with chronoportation, however.  To chronoport, each unit must be explicitly given the order to chronoport.  This is generally not a problem, unless you forget and just order your group leader to time travel, in which case you’ll watch him head off solo, leaving his bewildered subordinates behind.  Once you fire off a chronoport (regardless of the number of units involved), the ‘porter has to recharge, which means you either need to wait to send the rest of the units, or back up time, clear the original order, select all the units, and re-chronoport (if you have enough chronoenergy to pull off the retroactive command).  Again, it kludges up the fun part of the game.  I’m sure the reason for doing this was to close off some weird paradoxical exploit, but it’s still frustrating.

Other, more standard mechanics are implemented well.  There’s unit production queuing, order queuing, a form of hierarchical grouping (actually pretty sophisticated), hotkey control groups, and pretty much all the basic RTS interface conveniences are in place and function as expected.

Gameplay

Balance seems fairly straightforward, since the three factions are very similar in terms of the capability of their units, and I didn’t notice one side feeling particularly overpowered compared to another (although Vecgir teleportation, as mentioned earlier, is very handy).  Generally technology research costs way more than production facilities or units.  Unfortunately, I don’t have enough of a feel at present as to whether rush tactics are viable or if the game requires a more economic opening strategy.  It did seem difficult to build up a quick rush, but that might just be my ignorance of proper strategy.

The real gameplay sophistication comes from time manipulation, of course.  The Achron wiki reads like a cross between a quantum mechanics textbook and a medieval grimoire, with page after page of detailed analysis on the intricacies of various time travel strategies, including one ritual designed to permanently clone units that’s effectively a NOT logic gate capable of sending information to the past.

In general units tend to move pretty slowly on the map, although you can always put the game into fast-forward to make the units move more quickly.  If you get ambushed when speeding through things, you can always jump backwards and take care of the problem.  And really, for a game where you control time, it does seem like you spend a lot of time just waiting for time waves to propagate and the resultant stuff to happen.  Again, this could just be my low skill level….

Conclusion

Although there are a lot of aspects of the game that fall short of perfection, Achron is absolutely unique in what it does.  No other game has tried anything as ambitious as a 4-way real time strategy game where any and all of the players can make changes at any point in the game’s timestream.  When you think about it, it’s just amazing that Dr. Hazard (the perfect name for a mad-scientist game developer) and his team managed to pull this off as well as they did.

With the benefit of hindsight, I wish they’d have scaled back the game, focusing on a more limited set of RTS features, and doubled down on the time travel.  Achron‘s hook is time travel — they would have been better served to go all in.  With a game that was more of an intriguing temporal puzzler, focused on using a few units rather than building bases, the concept could have more fully explored the ramifications of time travel, and not gotten bogged down in all the details of implementing a full RTS.

All that said, however, I really recommend you check out Achron.  Hazardous Software deserves kudos and support for making such an amazingly groundbreaking game, and even if Achron is not the absolute best RTS ever produced, it’s still well worth checking out to see what it’s all about.

Tags: Computer, Game Design, Game Review