The Tau Empire aresenal is filled with a lot of high S/AP weaponry, most with very specialized roles such as anti-tank (Railguns, Fusion Blasters, Plasma Rifles, etc.), anti-MEQ (Vespid Neutron Blasters, Rail Rifles, Missile Pods, etc.), or just plain old anti-everything-else (Pulse Rifles, Burst Cannons, Smart Missile Systems, and just about every other S5/AP5 gun out there). There are also certain "random" helper weapons, such as the famed Markerlight Target Designator and the almost never used flechette discharger.
The tricky thing here is that, while most of the commonly employed Tau weaponry are effective against infantry due to their high S/AP, most of them just don't have the necessary rate of fire to deal with larger infantry blocks. Sure, a burst cannon's S5 AP5 will deny most non-MEQ infantry an armor save, but each burst cannon only has 3 shots at mostly BS3, and doesn't really come in bulk, truth be told. A 6-strong Stealth Suit squad can crank out a hiddeous 18 shots per turn with their Burst Cannons - but, at BS3, we're looking at a statistical 5-6 wounds on basic, bulk-underpants infantry. Not great odds when there's another 100 or so more ready to step up and take their place.
Since the weapon makes the Tau, in this instance, lets go through all the Tau weaponry that IS effective against massed infantry, ranked by availability. (To avoid a GW lawsuit/face slap, I'm not including points values).
Shas'O/Shas'El/Shas'Vre Battlesuits (i.e. access to special issue)
Airbursting Fragmentation Projectors - S4/AP5, G18", large blast and denies cover
- One of the three blatant exceptions to the normal theme of Tau weaponry, this fella is flat out designed to be anti-infantry. Only 1 shot a turn and special issue (i.e. you can only have 1 in a list), the AFP gives you a massive template of cover denial, and throwing this thing on a BS4/5 commander means you've got one heck of a potential Guard killer. Rank = A++
Cyclic Ion Blaster - S3/AP4, 18", assault 5
- The second exception to the trend, the Cyclic Ion Blaster is another special issue anti-infantry that would actually pair pretty well with the AFP on a Commander or, better yet, one of his Shas'Vre bodyguards. Low Strength means you'll have a problem or two with MEQs, but even Guard command squads will come to fear this little do-hicky thanks to its more substantial armor save denial. Rank = A+
Crisis BattlesuitsBurst Cannon - S5/AP5, 18", Assault 3
- one of the many SAP-5 Tau weapons, the Burst Cannon is still a very effective infantry killer due to its 3 shots per turn, and excells at killing the average 5+ armor save infantry. However, even on the cheaper Stealth Suits, you're going to have to kill 5-6 Guard per suit to make up their points. Rank = A-
Flamer - S4/AP5, template, Assault 1
- the humble flamer is the third trend-breaking Tau weapon, and much more common among 40k armies as a whole. The template weapons can wreak havoc on massed infantry, and the undesirable need to be incredibly close to the enemy is mitigated by jump packs and a high survivale rate against basic, non-upgraded or power weaponed infantry. Great for busting those hard-to-kill units out of cover, and even Twin Linked, its also really, really cheap! Rank = A
Missile Pods - S7/AP4, 36", Assault 2
- While generally more of a MEQ killer, what the missile pod lacks in comparable rate of fire, it makes up for in range and save-denial. Good at focusing fire on HQ or Elite infantry without fear of immediate reprisal, its still on the mildly expensive side, and fire warriors are nearly as effective. Rank = C-
TroopsPulse Rifle - S5/AP5, 30", Rapid Fire
- the most famous of Tau weaponry, the SAP-5 Pulse rifle is the mainstay of the Fire Warrior arsenal, and a good anti-everything gun. The lack of a higher rate of fire is mitigated by the cheap cost of Fire Warriors, long range, and the rapid-fire option (though getting that close with fire warriors is always a gamble). Pulse rifles are one weapon Tau can bring to the table in force. Rank = A+
Kroot Rifle - S4/AP6, 24", Rapid fire, counts as +1 hand weapon
- Kroot themselves are highly effective anti-infantry (IF they get the charge), and the Kroot Rifle is a good weapon for them - getting in close with Kroot is the point, and having rapid fire and +1 hand weapon really helps with this. However, as cheap and effective as kroot are at assulting, even basic guard can shoot them to a quick and early grave. Best as a backup to more dedicated shooting. Rank = A-
"Ferocious Fangs"
- Strangely enough, one of the only (effective) close combat weapons mentioned in the text, they aren't on the weapons sheet, and don't actually do anything outside of the normal stats for their originators, the Kroot Hounds. These are worth mentioning simply because Kroot Hounds are basically weapons in and of themselves - they can only be added on to a Kroot squad, and are slightly more effective (and cheaper!) than Kroot at combat, but don't have a ranged weapon. Guard squads will quail before these guys (again, IF they get the charge). Rank = B+
Pulse Carbines - S5/AP5, 18", assault 1, Pinning
- nowhere near as effective as Pulse Rifles, carbines are worth mentioning solely for their pinning ability - which most armies have ways of ignoring anyway. Target a lonely basic Guard squad and they have the potential of delaying them, at the very least. BS2 Gun Drones, with Twin Linked Carbines, are mobile and ignorable enough to make these worth it for versatilities sake. Rank = C+ (on Drones)
Vespid Neutron Blasters - S5/AP3, 12", assault 1
- the under-used MEQ killers of the Tau List, Vespids' weaponry is only matched by their incredible agility at covering ground - Jump infantry with the 'Fleet (of wing)' special rule and the ability to re-roll failed dangerous terrain tests, these fellas can fly circles around most other infantry squads while laying into them with some very effective AP3 shots. Their 5+ save, T4, and I5 make them a decent CC strike team against weaker targets of opportunity, but throw in a Strain Leader and they've got Ld9! Although they're easily the most expensive non-battlesuit infantry in the Tau list and only have 1 shot a piece, their massive combat mobility (especially when combined with Kroot) is just too good to pass up. Rank = A
Rail Rifles - S6/AP3, 36", Heavy 1, Pinning
- available either on Sniper Drone Teams, or as upgrades to 1/2 a Pathfinder unit, rail rifles have never quite seemed in the right place for me. Up to 3 Sniper Drone teams take up a single Heavy Support choice, but that's normally better suited to another Hammerhead; and putting them on pathfinders costs more and negates the markerlights! You get 3 Drones and a Networked markerlight per Sniper team (so a potential 9 BS4 shots, using markerlights), though, and for long range precision, nothing beats that. A lot of Tau anti-infantry can be considered sledgehammer-like, so having a bunch of precise, mid/long range, save-negating, command/character killers could potentially be VERY lethal against infantry armies such as iGuard. Rank = A-
Markerlights - S-/AP-, 36", Special
- Nothing much to say here - markerlights don't actually do damage themselves, but given their ability to boost friendly BS and eliminate enemy cover, they can make other shooting MUCH more effective. Pathfinders are the most points-effective method of using them, and I'm on the fence about whether or not another squad and a half of fire warriors isn't more effective for the cost. They've got their place. Rank = B-
VehiclesSmart Missile System - S5/AP5, 24", Heavy 4, Ignores Line of Sight
- SMS are another SAP-5 Tau mainstay, and prove themselves highly effective on both Devilfish and Broadside Battlesuits (not really a vehicle, but close enough). Their range and ability to shoot at ANYTHING within 24", even outside of line of sight (although this gives the target a cover save) is nothing to laugh at, but with only 4 shots a piece, it adds up to a very expensive option. Rank = C+
Hammerhead Railgun Submunition - S6/AP4, 72", Heavy 1, Large Blast
- available only on the Hammerhead Railgun, this blast template is startlingly effective against most types of infantry, especially at long range, but comes at a pretty high cost - I usually run Hammerheads at over 160pts! For an infantry killer, this bugger has one huge threat area, but most skilled enemies aready know this, so are less likely to cluster, even in their deployment zone, but with only 1 shot a turn for its cost, has some downsides. Rank = A-
Flechette Discharger - CC, Special
- often ignored, this add-on to Tau Vehicles isn't technically a weapon, though what it does can be almost as effective - any enemy model assaulting the vehicle take a wound on a d6 roll of 4+, with saves allowed, before combat begins. Given how often enemy infantry have assaluted my tanks, I'm surprised I don't take this more often, but its points value and relative ineffectiveness against MEQs' armor saves makes it less likely to recoup its points. Throwing it on a Devilfish (which is likely to get in close) might be a good option, especially against Guard, but for its points, not a mainstay on most of my tanks. Rank = C
Well, that's the weaponry I think will matter in this case. I'm deliberately not including Etherial CC weapons, or a bunch of Battlesuit weaponry, simply so save space on an already LONG post (and I consider Etherials to be useless to my style of play). After reviewing it all, there's quite a bit in the Tau army that has the potential to be anti-infantry (if used right), and I'm man enough to admit I was a little off in my earlier presumptions.
Taking Ranks, potential, uses, and how they all fit, here's what my top choices for things to make room for in my Anti-Guard/Anti-Infantry list, and why.
1). Vespids - mobility, mobility, mobility, and utter lethality
2). Airbursting Fragmentation Projector/Cyclic Ion Blaster - the best choices out there for modifying my command team.
3). Sniper Drone Teams - lots of potential at killing commanders/comissars/etc.
4). Kroot/Kroot Hounds - very effective against infantry, and good at protecting snipers/fire warriors.
5). more Fire Warriors - versatile and cheap anti-infantry fire, they can take out the whole gamut of stuff thrown down, and with Kroot to back them up, don't need Devilfish.
I'm pretty much set with a mainly Static build in my anti-Guard list - less vehicle-focused (no devilfish) while remaining agile (Vespids and Battlesuits), and more ability to lay down a withering hail of fire (fire Warriors, Sniper Drones, and Stealth Suits) with good combat backup (Kroot). Some of these may get cut in favor of a more generalized feel, but I'm trying to stay focused on the "tailored list" idea (also, given the Guard preference for tanks, a Hammerhead and a 3-strong Broadside contingent with target locks (fire at different Targets) are almost a certainty). We'll see.
Wow, this was an incredibly long post.