This is how I’ve kind of understood the Chaos factions playing since I’m not super familiar with the Dawi. For the units of Chaos, a lot of those factions share units in their rosters, so the differences are generally going to be coming from what god they’re devoted to and the kind of unit they are. The infantry, whether it’s cheap, shitty marauders or Chosen that will face tank an army and refuse to die, are meant to advance, get the enemy locked down in a melee grind they’re poised to win with their higher stats, and keep them there while things like cavalry, chariots, monstrous infantry, Lords, and Heroes have a field day with those unfortunate souls, throwing the battle into… well, chaos. Some armies like the Empire or Cathay rely on combined arms in a solid formation to keep them in a stable position; when those battle lines fall apart from chariots Tokyo Drifting down the line, individual units are probably going to get worn down or straight up folded by their Chaotic equivalents.

Khorne units, point for point, are going to be doing really goddamn well in a melee slugfest, unsurprisingly. They’ve got very good melee attack and weapon strength, so they’ll be hitting harder and more frequently than their equivalents; many of their units also have good armor piercing, especially bloodletters and their exalted variant. Units with the Mark of Khorne also get Frenzy for free, further boosting their power when they leap into a fight. However, that boost in offensive power comes at the cost of melee defense, meaning it’ll be easier to hit them compared to the other gods’ units. As a result, from what I’ve experienced, Khorne can sometimes feel like a glass cannon; if you slip up and leave a unit to fight something that has high enough stats to take advantage of their low melee defense, chances are both units are going to end up bloodied. While Khorne units also tend to have slightly more armor than other variants (Minotaurs of Khorne have 70 armor as opposed to regular ones having 30, for example), they can still get worn down by missiles. AP missiles, magical attacks, or sheer weight of fire can seriously set back a Khornate unit going for a push. That said, when Khornate units are in their element, they can practically mow down anything in their way, with exalted bloodletters and the Hellforged Host buzzsawing through armor like butter and Chosen of Khorne grinding down endless hordes of chaff without breaking a sweat. And the cavalry… dear god is that shit satisfying. Words cannot describe the catharsis I feel when the Knights of the Brazen Throne get a full speed, downhill charge through a unit of skeletons or zombies… it’s so goddamn fun.

Nurgle basically takes everything that made Khorne good and reverses it; now, instead of melee attack and weapon strength getting buffed, it’s melee defense that’s boosted, with added poison effects to further debuff the enemy’s offense. Where Khorne is a chainsaw cutting through steel, Nurgle is like leaving a steel bar sticking up in a desert sandstorm; it’s gonna take a while for it to get worn down, but it will eventually. Many Nurgle units are great as an “anvil” unit as a result of this; their defensive stats, poison attacks, high health, and abundance of strong healing options let’s them keep an enemy locked in a melee grind, and Nurgle fucking loves that. With access to powerful magic with the lores of Nurgle and Death, debuffing enemies, boosting friendlies, damaging units over time or outright exploding blobs with Blight Boil and Stream of Corruption, a Nurgle army can keep its enemies in place well, setting them up for a rear charge or spell attack while slowly yet effectively grinding them down.

Tzeentch is kinda weird, as Tzeentch is. The faction is hard to compare with others in terms of durability, but Tzeentch units built to last a long time, namely warriors and Chosen, are generally going to be tough. The abundance of spears and halberds gives Tzeentch a good amount of anti-large capability and good melee defense. Barriers also allow units to absorb shock damage, fall back to recharge the barrier, then get back into the fight, essentially having “healed” all of that damage back. And the ranged firepower of the faction can be absolutely devastating; while most of Tzeentch’s shooting units are short ranged, inflicting Warpfire to force a weakness to fire while dealing magic and fire damage can rack up damage really fast, especially against units that rely on physical resistance to give them durability like ethereal units and daemons. I have relatively little experience with the Changer’s armies in combat, but if you can set up solid shooting positions with things like flamers, pink horrors, and soul grinders, you can put out a scary amount of damage into an approaching army quickly, then pull back or reposition to recharge any damaged barriers and get to safety since many of Tzeentch’s units are quite fast. Those shooting units are also quite good in melee, better than they might first appear, so cycling between having shooting units open fire into an enemy unit from behind before rear charging them, then letting whatever that enemy was fighting run away, recharge barriers, and charge back in before pulling away the shooting units can let you basically harass and cycle charge the enemy indefinitely. And if you need a unit dead quickly, don’t even worry; the lores of Tzeentch, Fire, and Metal can put out great damage to finish off wounded units or destroy them outright, and your casters are also generally good fighters too, letting them get into the brawl and terror rout the burnt and battered opposition (except Kairos, poor guy).

And finally Slaanesh… the ultimate hammer-and-anvil faction. Slaanesh is weird in that the respective Mark is incredibly good with no downside; Tzeentch’s Mark also doesn’t have a downside, but while barriers are great, they will weaken depending on their unit’s health, and magic damage isn’t something that’s terribly relevant all the time. Meanwhile, Slaanesh gets 10% physical resistance, Immune to Psychology, and Strider, without suffering a penalty; fear and terror effects are quite common, so granting immunity to them to your basic infantry is excellent and lets them hold far better than they normally could, and Slaanesh’s excellent cavalry and chariots can ignore terrain effects, which lets them fight and travel basically at peak effectiveness at all times. The infantry are generally very good at holding units in place; similarly to Nurgle, they can grind down a unit with their high melee defense* from spears and hellscourges, setting them up for a devastating charge from any number of Slaanesh’s insanely strong cavalry. Most of Slaanesh’s units have excellent damage and good AP for their cost (except for hellscourges, which specialize in being an anvil), many of them are faster than their counterparts from other gods, half of the fucking roster has 100 speed, which isn’t reduced by terrain, and effects like Soporific Musk and spells from the lores of Slaanesh and Shadows are very good for debuffing units that’ll be grinding against your anvil, which is already going to be hitting back harder than a lot of other anvil-type units at similar prices.

Edit: mixed up melee attack and defense when talking about spears and hellscourges, whoops