The Tau Codex has a lot of leaks out there, but this one is written out with as a summary of various things that should look interesting for you.
on reddit via u/burningfreedom4 summarizing the leaks from Codexcat. Codexcat has shown us that the codex is in hand before, but I don't know just how real these are.
This is going to be a really long post. All credit to u/CodexCat
I split the contents between groups of statblocks, weapons, wargear, stratagems, traits, and other in that order. I tried to keep rules for the same units together, but besides that, good luck lol
Statblocks:
Longstrike is BS 3+, Fireblade as well. Commanders are 2+. Everybody else is 4+. Drones are 5+ natively. Firesight Marksman is BS 3+ for his pulse pistol. He makes a unit of sniper drones BS 3+
Commander:
Enforcers have 2+ baked in and -1 dmg (the only source in the codex) Master of War: RR1s to Hit for <sept> Core units aura on Commanders
Coldstar Commander:
M14, which you can boost with the Tau sept relic (+2" mv, can reactively moved when charged, opponent can choose new targets) or the Vior'la sept trait on the first turn. Otherwise, you just advance d6"
Drones:
Shield drones do not have FNP. Stealth drones: Unit cannot be targeted if greater than 18" away. Recon: Has a burst cannon. Gives Ignores Light Cover to its unit. Grav-Inhibitor: - 2 to Charge rolls against this unit Pulse Accelerator: All pulse weapons improve AP by 1 in this unit
Ghostkeel:
Ghostkeel is M12, WS5", BS 4+, S6, T7, W12, A 3, LD9, Sv 3+ Can't be targeted if the attacker is more than 18" away (unless it's the closest eligible model.) Ranged attacks are always at -1 to Hit. Comes with a Drone Controller stock for that 6" Saviour Protocols save. Flare Launcher gives 5+++ vs. Ranged attacks with S7 or more You can give the Prototype Early Warning Override that allows you to shoot out of phase at something that's come out of Reserves within 12" (choose between this and the Flare Launcher, unfortunately) They have M12 and Fly, so they can shift with Strike and Fade if you need to.
Pathfinders:
They get a Drone controller which is good if you want to take drones in the unit because it gives them a BS 4+ (up from 5+) , a grenade launcher (S6, Ap-1, 3 Dmg, or an EMP that makes vehicles play at 1/2 wounds for their degrading stats for the next turn), the Neuroweb system jammer that gives them a Keyword to be eligible to use a strat that no other unit could anyway...
Farsight:
has A5 and does that "Choose Double weak attacks or Single, 2x 3 dmg attacks" that all the real characters do now.
Sunshark: is all damage output. 12 Ion Rifle shots that can overcharge.
Riptide:
Riptides are Heavy Support now. They have a 4++. The Reactor gives choice of 5+++, 2d6 move in the charge phase (but no charging afterward), or extra shots with main gun. (4 for Heavy Burst, 2 for IA)
Kroot:
all get a pre-game 7" move and an additional +1 if they're getting Light Cover. They're S4, A2 WS3+, AP-1. There's a relic for Shapers to give them +1 S & A (It's a once-per game aura, like an SM banner)
Vespid:
WS 4, BS 4, S4, T4, W1, A1, Ld8, 4+ sv
Stealthsuits:
Stealth suits are mostly the same. Burst cannons get 2 more shots, and the FB gets the melta rule. Stealth rule is -1 to hit ALWAYS and +1 to saves when in cover vs Ranged Attacks. Homing Beacon lets you pull Crisis Core units out of Manta Strike on turn one and deploy them within 3". I suppose that's pretty cool Stealths are 25 ppm. FB is +5, Homing Beacon is +5. Stealths are Elites
Stormsurge:
costs 330 pts, Built-in 4++.
Weapons:
Both types of FB get the new Melta treatment: +2 dmg at half range.
Hammerhead Railgun is the only weapon that ignores Invuls innately.
Seeker Missile: 72", Heavy 1, S9, AP -3, Dmg 2d3, one shot per seeker.
Pulse bomb seems alright. 6d6 dice, 4+ is a MW. Can go to 10 dice against large squads.
Vespid:
Neutron Blasters are 18" Assault 2, S5, AP-3, D2
Skyray:
Sky rays have a Seeker Missile Rack - 72", Heavy d3+1, S9, AP-3, 2d3 dmg
Stormsurge:
Driver cannon is Hvy 3d3, S10, AP-4, dmg 3, Blast. Cluster Rockets retain Blast ability
Ghostkeel:
CIR is 36" Heavy 6, S7, AP -2, D2. The overcharge version is +1 S and Dmg as normal. Fusion Collider is 24" Heavy 3, S9, AP -4, D6, +2 dmg in half range
Crisis suits:
Plasma rifle is Assault 1, S8, AP-4, Dmg 3.
Points increase for each successive duplicate weapon. For instance, Fusion blaster: +10/+15/+25 A 3x FB Crisis Suit costs 80 Points. Further, 3x3 FB suits cost 240, 3x3 CIB costs 255, 3x3 PR costs 180: Total 675 for 3 squads. Or 9x FB/CIB/PR suits @ 55 ppm: 495 points
CIBs are AP -2 now. I think all Ion weapons are.
Airbursters are 24" Assault d6, S4, AP -1, D1, Blast, Line of Sight not required
Onager Gauntlet is S 2x, AP -4, Dmg 3. You can use all your attacks.
Pirahna:
The burst cannon is AP 0 base. The fusion blaster is a heavier, vehicle-mounted specifically for the piranha.
Broadside:
Rail Rifle Heavy 2 S9, AP -4, d3+3 damage, 1 auto MW on successful wound.
Hammerhead:
+10 for Ion Cannon (Heavy 3d3, S7(8), Ap -2, D1(2), Blast)
Riptide:
Ion is flat dmg 3, overcharge to 4. Flat 6 shots, Reactor can boost this to 8. Each roll of 1 causes a MW to the Riptide when you overcharge. HBC is Heavy 12, S6, AP -2, D2. Reactor boosts this to 16.
Pathfinders:
Pathfinder rail rifle Heavy 1, S8, AP -4, 3 dmg, +1 MW if wound roll succeeds. 5 points
Farsight:
Farsight's dawn blade is double profile: S 2x, AP -3, Dmg 3 or S+1, AP -2, D1, 2x Attacks He has base A5
Wargear:
Drone controllers boost the range to within 6"... but SS and Riptides can't have them. No vehicle systems. Closest you get is buying seeker missiles, I guess.
Crisis systems are as follows:
Counterfire Defense System - Get the keyword to use the strat. Mercifully, does not cost points
EWO - 5+ Overwatch for this model. The Overwatch Stratagem costs 1 less CP when used for this unit. Also free. Probably need to have at least one of these per Crisis team.
Iridium - 2+ save, 1 per 3 models, 10 points, does not take up a support slot!
Multi-tracker - 6s to hit score an additional hit for ranged attacks targeting units containing 6 or more models. Free as a bird.
Shield Generator - 4++, 5pts for Crisis, 10 pts for Commanders, built in to Stormsurges and Riptides! Ghostkeel cannot have.
Target Lock - This model Ignores Light Cover Velocity Tracker - Ranged attacks gain +1 to hit when targeting units with the Fly keyword
Point buy relics:
Wide-Spectrum Scanners: +20pts Model equipped with Early Warning Override only. At the end of the Reinforcements Step of your opponent's Movement Phase, if the bearer is not within Engagement Range of any enemy units, it can shoot as if it were your Shooting Phase, but it can only target a single eligible enemy unit that was set up as Reinforcements this turn and is within 12" of the bearer.
Internal Grenade Racks: +15pts Once per turn, after this model has moved in your Movement phase, select a unit it moved over and roll a d6: on a 2+, SMITE THEM (d3 MW)
Resonator Warheads: +30pts Commander or Crisis only. Replace a Missile Pod with the following: 30" Assault 3, S8, AP-2, D2. Any Infantry, Beast, or Cavalry unit hit by this weapon halves their Move characteristic until your next Shooting phase. (Cannot reduce Move to less than half, if combined with other similar effects. I don't know where those effects are in this codex, I'll have to dig for them)
Stratagems:
There is a stratagem that allows a unit to hop out of a devilfish after the devilfish moves. Saviour Protocols is a Stratagem. It works on ANY unit (that has the same Sept as the Drone), but the drone model must be within 3" and dies as part of the strat.
There is a Strat that allows you to shoot at things out of LoS with seekers if they have a markerlight token (and you get +1 to Wound for the attack)
Drop Zone Clear remains the FSE strat (full Hit and Round reroll and Drop Threat Acquisition is the same cost but only works for Hit rolls (and every sept can use it)
Coordinated Engagement - 1 CP Use in your shooting phase, choose two units and an enemy unit within 18" of both. Your units can only shoot the Victim and they get +1 AP for all their attacks against him for the rest of the phase
Breachers have the Sweep and Clear Strat (Ignore cover, reroll wounds), Strikes have the Relentless Fusillade Strat (Ignore Rapid Fire rules, double shots, additional point of AP), BOTH can use Pulse Onslaught (unmodified 6 to Hit auto wounds the target) They can use Point Blank Volley (Pulse weapons are Pistol 2) if... like, somebody charged you as a joke or you want to waste a CP
A strat gives a RR1 to hit aura to a devilfish that only works on Fire warriors.
Bork'an stratagem allows a single weapon to ignore invuls when attacking for 2 CP
Traits:
Warlord Traits!
Precision of the Hunter - Character gets full Hit and Wound rerolls. This is excellent.
Through Unity, Devastation (Aura) - Friendly <Sept> Core units within 6" get +1 AP on unmodified Wound Rolls of 6
A Ghost Walks Among Us - -1 to Hit the Warlord, Don't roll Advance increase Mv 6"
Through Boldness, Victory - Command Phase, select <sept> Core unit within 9" Until you next command phase, Core models in that unit making ranged attacks automatically wound on unmodified hit rolls of 6
Exemplar of Kauyon - If you chose Kauyon, redeploy 3 <sept> units after determining who has the first turn. Otherwise, choose 1 <sept> unit
Exemplar of Montka - Command Phase, choose a <sept> Core unit within 9" of this Warlord. Until the start of your next Command phase, Core models in this unit making ranged attacks that target enemy units within 9" (12" if you chose Montka) can reroll the wound roll.
Kroot Traits:
Master of the Hunt (Aura) - Kroot units within 6" ignore cover with ranged attacks against enemies within 12"
Pack Leader (Aura) - Kroot units within 6" roll an extra d6 and discard one when charging
Nomadic Hunter (Aura) - Kroot units within 6" of the warlord count as Remaining Stationary for ranged attacks, unless they Fell Back
Sept Traits:
Tau - 5+++
Vior'la - Academy Luminary - While on the battlefield, each time you spend a CP to use a Tau Empire Strategic Ploy or Wargear Stratagem, roll a d6. On a 3+, your CP is refunded.
Sa'cea - Strategic Conquerer - In your command phase, select a sa'cea unit within 9". Until the start of your next command phase, that unit has Objective Secured. If it already has that ability, COUNTS AS DOUBLE MODELS
Dal'yth - Unifying Influence - two auras, Diplomatic Excellence is +1 Ld to Dal'yth and Aux units. Integrated Command Structure is Aux units within 6" can use Markerlights
Bork'an - Seeker of Perfection - Each time the warlord makes a ranged attack, +1 AP, unmodified wound roll of 6 is addition MW (max 3 per phase)
FSE - Master of the Killing Blow - On ALL attacks, unmodified wound of 6 is +3 AP, wounds cause by this model's attacks cannot be ignored by FnP type rules
There are 6 septs.
Tau - reroll 1 hit or 1 wound when a unit attacks, +3" to Auras, Litanies, Targeted buffs
Vior'la - +2" mv when wholly in your deployment zone on your first turn. Reroll Advance and Charge rolls.
Sa'cea - Ranged Attacks targeting VEHICLES get Dense Cover if attacker is more than 18" away. Ranged Attacks targeting INFANTRY (and everything smaller than a Ghostkeel is INFANTRY) get Dense Cover if attacker is more than 12" away. VEHICLES and BATTLESUITS do not suffer the penalty to firing Heavy weapons at targets within Engagement Range of them.
Dal'yth - Ranged Attacks against Infantry have Light Cover unless they are within Engagement Range of the Attacker (so... fear the Dark Angels, I guess?). Aux units get your selected Montka or Kauyon.
Bork'an - +4" range to all guns. Ranged Attacks against Battlesuits and Vehicles of S7 or lower get -1S. It's like Ramshackle but worse in almost every way.
Farsight Enclaves - Always have Markerlight if making attacks within 12" Seems to be the only time to get marker benefits in the charge phase. Reroll 1 Wound when a unit is chosen to shoot or fight.
Other:
Free overwatch is DEAD for most units. Group overwatch is DEAD for all units. Core units are Fire warriors of both types, Pathfinders, Crisis suit teams of both types, Broadsides, Stealths.
Dal'yth is the only Sept that buffs Aux units. No build-a-sept traits modify them.
Nova Reactor no longer has a risk of damaging the model. Instead, it burns out for the rest of the battle if you fail the test. Branched Nova Reactor turns a failed test into a success.
I think FS can take Aux units. It's written strangely in comparison to the Tau Empire detachment rules directly above it. They can't take Ethereals and Ethereals are very carefully restricted from buffing them. there are no stratagems that modify Montka or Kauyon (which I thought would have been a gimme for the rules team) by advancing or rolling back the turn number for a specific unit or giving the OTHER one to a unit for a single phase or something.
Farsight gives the same buff as a standard XV8 Crisis Commander: Tactical Acumen Shadowsun and Farsight don't affect them (montka/kauyon). They have the exemplar warlord traits, which get better if you chose that Philosophy. Farsight: He also can choose a Farsight Enclaves Core unit at the beginning of the Fight phase and give them +1 to Hit in Melee for the phase. Shadowsun has Full Reroll Chapter Master Buff, does not break Sept Traits if she doesn't match the army, and is a Supreme Commander. BOTH have RR1s to Hit for Core aura.
Each time a model in that unit makes a ranged attack against a unit with one or more Markerlight Tokens, add 1 to that attack's hit roll.
After that unit has finished making attacks, for each enemy unit targeted by those attacks, remove one Markerlight token from that enemy unit. Remove all Markerlight tokens at the end of your shooting phase The action: You roll a die for every markerlight. On a 3+ you put a markerlight token on a unit that is an eligible shooting target. Start of movement to Start of Shooting. Pathfinders have an exception that allows them to start the action at the END of movement phase.
Fire Markerlights (Action): One or more Markerlight units from your army can start to perform this action at the start of your movement phase. Aircraft Markerlight units can perform this action. The action is completed at the start of your next shooting phase. If this action is successfully completed, for each model in that unit that is equipped with one or more markerlights, for each markerlight that model is equipped with, select one enemy unit within 36" of that model that would be an eligible target for that model if its unit had been selected to shoot, and roll one D6: on a 3+, that enemy unit gains one Markerlight token. While a VEHICLE or DRONE unit is performing the Fire Markerlights action, that unit can move without that action failing. If it does, until the end of the turn, models in that unit without the VEHICLE or DRONE keyword that are equipped with any markerlights are treated as not being equipped with any markerlights for the purpose of the Fire Markerlights action.
3 sniper drones attached to a Firesight Marksman. He buffs them in the Command Phase. You could use a stratagem to split them off into their own unit, if you like, but he has to be within 6" to give them BS3+ and MWs on 6 to Wound
RR1 support for non-Core is gone from the codex, so the Ion feels REAL dicey, as they still give 1 MW per 1 rolled, rather than a single MW IF a 1 is rolled at all. Same goes for Ghostkeels (I got a tingling down my spine and didn't overcharge. 4 1's on that hit roll. Felt pretty smug) Ion Hammerheads, CIBs, Razorsharks... Sunsharks have Ion Rifles, which cap at 1 MW per weapon. Their damage degradation is subtly worse than models with the same stats. A Hammerhead hits bottom profile at 3 wounds remaining, while a Riptide hits at 4. Both have T7 and W14. Everything but the Ghostkeel degrades ALL the way to BS 6+ now. I don't know why the Keel does, but I'm wagering on GW forgetting to update it.
Fireblade Volley Fire is an aura of 6s to hit give an additional hit for Core units with pulse weapons.
Ethereals have Invocations, which are just Litanies. Command Phase, goes off on a 3+, know 2, cast one. Relic staff gives additional cast and +1 to cast roll (like Master of Sanctity) Aun'shi and Aun'va have this relic baked in and know a 3rd litany to boot. Aun'va doesn't break sept traits if he doesn't match and has 6 W3+ S5, Ap-1, D2 attacks from his bodyguards, which might be JUST enough to bully those last two intercessors off the point. Aun'shi has a 4++, an aura that lets Core Vior'la units Set to Defend or Hold Steady when charged. Also, does not break Sept traits. AP -2, scores a bonus hit on hit rolls of 6s, A5
Storm of Fire - Choose a Core unit within 6", they can shoot without failing actions Sense of Stone - Core unit within 6", 5+++ Zephyr's grace - Core unit within 6", If they didn't Remain Stationary, ranged attacks are -1 to hit against them. Power of the Tides - Aux unit within 6", +1 to Wound rolls for all their attacks Unifying Mantra (aura) - Core units within 6" get reroll Morale tests and +1 to combat attrition tests Wisdom of the Guides - Gain 1 CP. The big money, right here.
Tau Secondaries:
Shadow Operations - Aerospace targeting relays Place a marker halfway along each battlefield edge. Units in your army can perform the following action Install Targeting Relay (Action): Infantry, start at end of movement phase, be within 6" of a different Aerospace Designation Marker. Complete at beginning of your next command phase or end of battle, whichever comes first. If successful, relay is Installed. Points awarded for number of relays installed 1 - 2 VP, 2 - 6 VP, 3 - 9 VP, 4 - 15 VP
Battlefield Supremacy - Decisive Action If Montka, +4 VP for Hold Half or More objectives at the end of your turn in Battle Round 1, 2, or 3. Nothing for 4 or 5. If Kauyon, +4 VP for Hold Half or More objectives at the end of your turn in Battle Round 3, 4, or 5. Nothing for 1 or 2.
No Mercy, No Respite - A Clean Victory If Montka, At the end of Battle Rounds 1, 2, & 3, you can score each of the following: +1 VP if an enemy unit was destroyed this round. +3 VP if 3 or more enemy units were destroyed this round If Kauyon, same as above, but for Battle Round 3, 4, & 5.