Infinity for 40k Players 2: Game Mechanics


Welcome to part two of my ongoing series of introductory Infinity the game articles. This edition covers game mechanics and how they differ from 40k but it will not teach you how to play the game. You'll need to read the Quick Start Rules or main rules (see the end of the article for links) to actually learn the game. The QSR are a good start but be aware that a few areas have been simplified in them and are slightly different in the main rules.

First off, here's a quick comparison of the dice requirements for the two games:

IGYG v. IGYG + Reactions

40k uses an I Go You Go structure plus move/shoot/assault phases with the other player taking no part (other than saving throws) in the movement and shooting phases. This can lead to the 'movement phase tea break' effect where you stand there watching your opponent moving units around until it's time to roll some armour saves.

Infinity also uses an IGYG turn structure but in effect all your models are on overwatch (if you've played Space Hulk, Epic or early editions of 40k) during the other player's turn. If the active player moves a model out into sight, your models will get to react to it by shooting, dodging, throwing grenades. This makes it a very engaging game but at the same time means that there is no letup during a game.


Phases v. The Order Reserve

In 40k's phase structure all the units will move once, then all the units will (mostly) fire once and then all the units will assault once. 

In Infinity there are no phases - instead, at the start of the turn you get an 'Order' for each model in your force and get to pool these Orders together to spend how you wish. Spending an Order on a model lets it take a couple of quick actions such as moving twice, moving and shooting, moving and making a CC attack or a single more involved action like indirect fire (called Speculative Fire) or laying down a suppressive fire corridor - one Order is similar to two Action Points in Space Hulk and there is a long list of different actions (called short skills and long skills in the game) including climbing, diving prone, dodging, shooting, throwing grenades, blowing holes in walls, laying mines and many more. Roughly speaking you can do two Move skills, a Move and a non-Move (also includes a non-Move followed by a Move) or a long action/skill but you can't make two non-Move skills, so no shoot-shoot Orders!

Once you've resolved all the effects of one Order you can spend another one. This can be on the same model, meaning that a single model can perform many actions in a single turn and also meaning that if all a turn's Orders are piled into one model it can potentially make it all the way across the board!

What stops this happening? Automatic Reaction Orders or AROs - each time you spend an Order on one of your models, every enemy model that can see the Order's actions gets to react. This means that a model walking out in front of multiple enemy models usually ends up like Butch Cassidy and the Sundance Kid running out in front of the entire Bolivian Army, in other words a bullet-riddled corpse.


Dice Mechanics

40k has many many types of mechanics to resolve actions including difficult terrain rolls, Run moves, to hit rolls, to wound rolls, saving throws and AP values, armour penetration if it's a vehicle, different types of to hit roll in CC depending if you're hitting a vehicle or model, Pinning, Morale & Leadership rolls, reserve rolls, scatter dice etc.

Very few of these rolls use modifiers, with conditions like cover being represented by an extra roll.


Infinity uses three types of roll. 

A 'Normal' roll where there is no opposing action by enemy models requires you to roll the appropriate stat or under on a d20. For example making a Climb action or short skill means rolling your physique (PH) or less. Any roll of exactly the number needed is a critical success, if this is an attack then it bypasses the target's armour! This is one reason why no model (even a Dreadnought equivalent) is safe from small arms fire.

Where you are performing an action that is being opposed by an enemy model (for example shooting at someone who is shooting back) this is a 'Face to Face' roll - all the models involved need to roll their stat or less but they also need to beat the opposing model's roll. Critical rolls in a FtF roll will beat the opponent's roll even if it's higher.

The third type of roll is an 'ARM roll' which is similar to saving throws in 40k as it is made by the owner of the model that has suffered hits. This is the opposite of the other rolls in that the player has to roll over the damage stat of the weapon. Here's one of Corvus Belli's video tutorials about face to face rolls.


Most rolls in Infinity will have some modifiers applied to them, for example ranged weapons have range bands with different modifiers, shooting someone in cover reduces the firer's BS by 3, low visibility areas like bushes and woodland reduce it by another 3, different types of camouflage can reduce it by 3 or even 6.

Let's take the Rifle and Combi-Rifle, two of the most common guns in the game.

Weapon Short Medium Long Maximum Damage Burst Type of Ammo Template E/M Vulnerablility
Rifle 0-8"/0 8-16"/+3 16-24"/-3 24-48"/-6 13 3 N No No No
Combi Rifle 0-8"/+3 8-16"/+3 16-24"/-3 24-48"/-6 13 3 N No Yes No

Measure the range to the target (note that all ranges in Infinity are centre-to-centre!) and see which range band you're in, the plus or minus after the range is the BS modifier.

We can see that the sweet spot for the Rifle is the 8-16" range where shots are made with +3BS but shots over 24" suffer a whopping -6BS modifier.

Taking the example of a standard line grunt with BS11 shooting at a target 14" away. If the target is in the open then the firer has BS14 and needs 14 or less to hit. If the target is in cover then it's back down to BS11. Go out to 30" and you're looking at needing to roll 2 or less (BS11 -6 for range -3 for cover).

A model's ARMour value acts as a modifier for the Damage rating of weapons hitting it and cover acts as an extra three points of ARM. So if a model with ARM1 is shot in the open by a Rifle they will need to roll over 12 to survive. In cover that will drop to beating 10 (Damage 13 - ARM1 -3 for cover). A TAG (roughly equivalent to a light Dreadnought) in cover plus ARM8 on the other hand only needs to roll over 2 (Damage 13 - ARM8 -3 for cover).


Death, Unconsciousness & Binary States

A quick note on states and model status in 40k & Infinity.

40k tends towards binary states -  a model is either alive or dead, fully functional or not functional at all. This carries through to most aspects of the game, for instace Apothecary's healing abilities don't let them heal a wounded model but instead give an extra chance of the model not being wounded in the first place.

Infinity works on the basis of multiple states, so a model reduced to zero wounds is not dead but is instead unconscious until healed by a Doctor or Paramedic. Only when taking a further wound is the model truly dead in game terms.


Orders & AROS in more depth

We've covered the basics of spending an Order on a model and opposing models getting reactions but it does get more complex in how you declare what's going on.

When you spend an Order on a model you have to declare what they are doing with their first short skill/action including the exact path if it's a Move. Any enemy models that can see (Line of Fire or LoF in Infinity terms) gets to announce a reaction (ARO). No dice are rolled at this point. You then declare what the active model is doing for it's second short skill/action including the exact path if it is a Move and any new enemy models that can see get to announce AROs. Finally, we resolve all the actions and roll dice.

As an example, Angus the Fusilier decides to Move with his first short skill, poking his head around the corner. The enemy model Wen Liu can see this and reacts by announcing a Shoot skill. Angus doesn't like this idea and announces a Shoot skill for the second half of his Order. The Order and ARO are now resolved by making a face to face roll between the models with the winner of the roll hitting the losing model. This can be a bit of a culture shock if you've only played 40k because your models can get hit and die in your own turn and without having fired plasma weaponry!


In the second example, Angus moves up to the corner and Wen Liu decides to Dodge in an effort to stop any incoming fire. Angus then decides to Move again to get across the alley into a better position as he now knows that Wen Liu isn't shooting at him.

At this point I should mention the Burst rating of weapons because this is the bit which stops the reactive player from wiping the floor with the active player's models whenever they try to do something by AROing them to death. The active model (the one having an Order spent on it) gets to roll a d20 for each Burst rating on the weapon but the reactive model only gets to fire back with one d20. So an active model with a Rifle gets to roll three dice compared to the reactive model's single die, making the active model much more likely to win the roll and therefore much more likely to kill the reactive model than to die.



Models in Infinity can see a 180 degree arc to the front. Until you get up really close (see Zone of Control), models can't react to models behind them meaning that you can shoot them in the back without them getting to shoot back at you. This is another of the things that makes positioning of models vitally important in Infinity.


Autohitting Templates

Just to confuse matters, 'Direct Template' weapons such as Light/Heavy Firethrowers and Chain Rifles (big shotgun-style guns that fire grapeshot) don't roll to hit, they just get to place a teardrop template coming out from the firer's base. This can make them suicidal to use as the target can choose to shoot and you won't be making any opposed rolls to stop their shots, on the other hand you've automatically hit them!

A quick note on sizes - Light Firethrowers using a template the same size as the Flamer template in 40k. Chain Rifles and Heavy Flamerthrowers use a larger teardrop which is ten inches long. 

'That's not a Flamer template, this is a Flamer template!'


Suppressive Fire, Reaction Robots 

There are a few ways of getting more than one shot back in ARO, the main one is to spend a complete Order laying down a suppressive fire corridor (it's a long skill so you can't move in the same Order). This is a 2" wide corridor going out to the maximum range of the gun and allows the model to react with the full Burst of the gun instead of rolling a single die. This is incredibly useful for channeling the enemy into specific directions.

The other method is to take a model with the Total Reaction or Neurocinetics skills which lets it always roll the full number of dice in ARO and makes for a very good defensive model. All th factions except for Ariadna have access to Remotes (telepresence drones/robots) with HMGs and Total Reaction while the Nomad faction also have access to Sin Eaters, infantry with Neurocinetics.

Total Reaction Remotes also have 360 degree visors letting them react to models approaching from any direction.


Weapon Ranges, Scenery & Close Combat

As we saw from the Rifle examples, weapons have much longer ranges then their 40k equivalents, especially compared to Rapid Fire weapons like Lasguns or Bolters. The negative modifiers can be punitive over 24" but if the target is in the open a model with a fairly standard BS of 11 is still hitting with 25% of their shots and each shot has a decent chance of taking down any model which isn't wearing powered armour.

As a result, most weapons fire tends to be limited by scenery rather than range, crossing a gap between terrain pieces can be risky business even if you're in the maximum range of any enemy guns.

Looking at longer range weaponry like HMGs or Sniper Rifles the range bands are terrifying:

Weapon Short Medium Long Maximum Damage Burst Type of Ammo Template E/M Vulnerablility
Sniper Rifle 0-12"/0 12-36"/+3 36-52"/-3 52-104"/-6 15 2 N No No No
HMG 0-8"/0 8-32"/+3 32-48"/-3 48-96"/-6 15 4 N No Yes No

Another area where positioning and movement is vitally important in Infinity is trying to stack modifiers in your favour, for example taking on a model with a Rifle by shooting at them with an HMG from 25-30" away - the Rifle model will be on -6BS for range and ideally -3BS for you being in cover while the HMG is on +3BS for range. If we look at basic BS11 Light Infantry in cover, an HMG in the active turn will be rolling four dice needing 11s or less while the poor target will be needing a 1 or 2 on a single die and desperately hoping for a Crit on a 2. In this situation it's far better for the target to Dodge against an unmodified PH stat...

For scenery, the recommendation for 40k is to have 25% of the table covered with terrain with a third of that being LoS-blocking terrain such as hills or complete buildings. In Infinity that amount of terrain will result in everyone dying as soon as they try to do anything because most of the enemy force will get AROs. As a rough rule of thumb any gap that needs more than one Order to cross (8" for most models) will be a killing zone and ideally you should have enough terrain on the table that you can't draw LoF from one player's table edge to the far table edge.

Here are some sample Infinity tables.

Finally, some GW Space Hulk tiles being used to represent a spaceship boarding action.

Don't worry too much if you're really short on terrain though, as there are a number of websites with free PDF downloads of paper scenery which will help fill a table quickly. You can also get a nostalgic feel for 'floor wars' by using cardboard boxes, piles of paperback books and whatever you have lying around to make a table to try out the game. A future article in the series will go into scenery in more depth.


So, close combat. Clearly, in a game that has Space Ninjas with monofilament lightsabers, giant Werewolves and slavering Highlanders with Claymores close combat must be really import, right? No, not really. You can make armies that are good at close combat but even then it's likely to be a situational tactic and not the driving force of the force, guns are just too deadly and AROs make it almost impossible to get into combat without being shot on the way in. 

A couple of tactics for getting into CC are the use of smoke grenades which can be thrown and block LoF until the end of the player's turn, the other is to have an infiltrating model hidden partway up the board who will wait for someone to get near and then leap out at them. See the camouflage section later on for hidden deployment.


Electronic Warfare

Other than the Tau, there is very little informational/electronic warfare in 40k apart from rare abilities like Imperial Guard advisors messing up your Reserves rolls. This is not true of Infinity. Other than the low-tech Ariadna faction, all factions have access to Hackers who can hack into robots, powered armour and TAGS and immobilise them temporarily or in the case of TAGS even possess them temporarily. If you ever played Shadowrun you have some idea what to expect...

Hackers can attempt to hack any Remotes, TAGs and non-Ariadnan Heavy Infantry within the Hacker's 8" zone of control even if they are not visible, making Hackers very good defenders against the advance of high-tech troops. However friendly Hackers can try and defend against hacks by the active model, leading to an escalation of electronic warfare.

Hackers can extend their reach through Repeaters which are carried by most Remotes and some infantry. there are also versions of Repeaters which can be left in place by scouts and ones which can be fired from guns. As each the Hacker gets to treat each Repeater's 8" zone of control as his or her own, covering patches of the table with areas that vulnerable troops don't want to enter.

Then there is electromagnetic (E/M) ammo. This can shut down higher-tech equipment such as Combi Rifles, anything that is hackable(Remotes, TAGs and Heavy Infantry) and even the Hacker's hacking deck, much like Haywire Grenades in early editions of 40k. If you scroll back up to the Rifle and Combi-Rifle statlines you'll see that the Rifle is too basic to be affected by E/M ammo while the Combi Rifle being a high tech weapon will be disabled by a successful E/M attack.

One of the final bits of electronic warfare is guided ammo and marked targets. Rather like the Tau Markerlights, models with the Forward Observer skill can light up a target which will let guided ammo be fired at it from outside LoF with no roll to hit. Marked targets can also be fired on by indirect weapons such as grenades and grenade launchers without suffering the normal -6 modifier for speculative fire.

The next level is often referred to as GML (guided missile launcher) spam and is a favoured tactic of the sneaky Nomads. Certain combinations of equipment and skills will let a model mark a target from outside LoF by getting up close within the 8" Zone of Control and making a Willpower check. A guided missile then homes in on the marked target and demolishes it, all without the target having seen everything. Hackers are again a defence against this as they can hack the missiles out of the sky on the way in.


Deep Strike v. Airborne Deployment

Where 40k has units arriving in a bunch via Deep Strike, Infinity has several levels of the Airborne Deployment skill varying from Parachutist which is similar to a called version of Outflank right up to Combat Jump where models can land drectly on the table as long as there is a flat space big enough to place a large blast marker. As you can imagine, managing to get a model landing in the opponent's back zone when they are all facing forwards can be a game-winner if they forgot to leave anyone guarding the area.

Another touch of electronic warfare - if a player with a Hacker suspects that there are Combat Jump models inbound, they can attempt to hack the aircraft and force the jumpers to leap out of the aircraft at the wrong moment with a much bigger chance of scattering.


Openness, Camo & TO Camo, The Lieutenant

The bit about the Hacker suspecting that there Combat Jump models in the enemy force neatly brings me on to secrecy. In 40k you know what is in the enemy force and which units are deploying normally, in Reserves or arriving via Outflank or Deep Strike. In Infinity you know about the models that are on the table. You know everything about them including what equipment and skills they have, but you don't know about Airborne Deployment troops until they arrive and you don't know about camo troops.

The Camouflage & Hiding skill again has multiple levels. Mimetism is the lowest and is roughly equivalent to Cameleoline, giving a -3BS modifier against incoming shots. camouflage is the next level and is enough to actually hide the model - instead of placing the model during deployment you place a camouflage marker which can't be shot until it reveals itself making an attack or by being Discovered through enemy Orders. In addition, an active model uncloaking gets to resolve it's attack before the target's ARO is resolved. Even when uncloaked, shots at the model suffer the -3BS modifier.

Thermo Optic Camouflage is the next level up. There is a -6 modifier when Discovering or shooting at the model unlike the -3 modifier for Camouflage but it gets even worse - you don't even place a camo marker instead of the model, you simply note down where the model has deployed as it is totally hidden until it moves or attacks.

Yu Jing Ninjas have TO Camo and lightsabers (Monofilament Close Combat Weapons). Whimper.

PanOceania have a TAG (the Cutter) with TO Camo. Double-whimper. 

The Shasvaatii of the Combined Army have a TAG with TO Camo, the Climbing Plus skill (think Spiderman walking up walls) and two Heavy Flamethrowers. Triple-whimper.

As you can see, there's quite a bit of leeway for hiding what is in your force, whether it's a mix of hidden TO models and AD troops or some combination of camo markers. 


The other hidden quality to your force is the Lieutenant. This is one of your models who gets an extra Order each turn but can only use it himself. Ideally you don't want the opponent to find out who the LT is because if you start your turn without an LT the number of Orders you can spend is capped at two! Electing a new (secret) LT costs two Orders. Only certain units can be chosen as the LT as options when building the list so there are two main options when deciding who should be the LT - one is to hide the LT among a bunch of similar models, for instance taking 3-4 identical Ariadna Line Kazaks and one of them is the LT, alternatively take a more obvious LT but make it something robust like a Heavy Infantry model that can take some punishment and make good use of the extra Order each turn.


How Much Do the Rules Cost?

They're freely available for download. So are the army lists. So is the army builder. The rules and equipment are also online in wiki format making it easy to look up specific rules. There is also a fan-made re-edit of the rules which combines the rules and equipment from the main rulebook with the extras from the Human Sphere expansion book and wraps it up with a bookmarked contents and index in PDF form, currently hosted by us.

The rulebook and Human Sphere expansion book are still well worth picking up as they contain a lot of background information not available on the Infinity website and contains large amounts of gorgeous illustrations.

If downloading the rules from the Infinity site you'll need the Rules, Human Sphere - Rules and Human Sphere Weapons List PDFs, the Quick Reference Sheet is also handy to have.

If downloading the combined rules PDF from our site it's also handy to have the Quick Reference Sheet from the official site.

The army lists come in two parts, Army and Weapon Lists from the rulebook and Human Sphere - Army Lists from the expansion.



One area where Infinity does fall down is missions - there are two official scenarios available but there are also large numbers of fan-made scenarios and mission systems including one that I'm currently working on. The next expansion book due sometime in 2012 is going to be a missions and campaigns book and it is eagerly awaited! 


New Player Errors

Finally, there are a number of rules questions and confusions that consistently come up with new players, I know as I made several of them myself when learning!

Dodges are different in the active and reactive turns. The main thing to remember is that a Dodge is not a Move skill so it can't be combined with another non-Move skill - you can't Shoot and then attempt to Dodge the incoming bullets in the same Order.

During AROs, Dodges still aren't Move skills but you need to make a Dodge roll against PHysique to be able to use Move skills in ARO and the distance will be halved.

So a Dodge in the active turn doesn't get you any extra movement while a Dodge in the reactive turn lets you make a half-move.

Face to Face rolls and multiple dice - the rules don't give a very good description of what happens when you are making a FtF roll and are rolling multiple dice.

The easiest is to start with the lowest dice rolls and work your way up. Time for an example. A Nomad Prowler is on the attack with a Spitfire (Burst 4) against a reacting Haqqislam Djanbazan Sniper (Burst 1 in ARO).

For the purposes of the example, both models are on BS12. Starting from the bottom, the Prowler start with a 3. This is a hit but it's lower than the Djanbazan's hit of 6 and is beaten. The 6 is in turn beaten by the 10 & 11 so doesn't hit. The 14 is a miss and is ignored. So the end result is the 10 & 11 hitting the Djanbazan who will now be making two ARM rolls and hoping for good dice!