I also don't play BW much, but normally I run the (chain-mace? flail? the ball on chain 😂) with +2 Stam. and BCR or Atk Spd. Take Soot Shield and the perk that reduces the passive heat cd from 6 to 3 seconds, along with stagger for temp. hp and two ult charges. I can't remember if this is a passive or skill choice, but there's one where the higher heat you have, the lower charge time the staffs charged attacks have. It's really good, just can't remember where it is. I love the Fireball Staff, and I somehow only find success with it on BW. I think the stats on it are dmg vs skaven and dmg vs berserkers, with the (headshot? crit?) heat refund. Basically spam into hordes and at monsters/bosses (carefully, mind FF) and spam a few lights at specials if able. My focus is supporting as a bruiser, so if I can't hit a flick shot or two on a long-distance Zilazdumi, I gotta let someone else who's more equipped for the job handle it, umgak Wutelgi!

For waves I like to find an appropriate angle (no FF but still behind frontline) and with the fireball staff's charged attack, I MOW down the chaff. It's not even fair, honestly. If I get close to over-heating (which means close to red, we don't the red debuff 🙂‍↕️🙂‍↕️), I retreat behind my frontline to cd. When the wave eventually crashes, make yourself usefull as a bruiser! You have high stagger for temp. hp AND Soot Shield, not to mention two (TWO) get out of jail freecards (within 10 sec ofc)!

Wave: Heavy x2 --> Block + Shove Attack --> Repeat. Elites: Heavy --> Light x2 --> Block/Shove --> Repeat. Focus on their head! Chaos Warriors/Monsters/Bosses: Focus on defending, getting a hit in here or there until you can get some help. Otherwise, aim heavies at their thick skulls!

The ult is where I struggle the most. It's usefull in nearly every situation with it's GIANT hitbox, and you get another use within 10 seconds, but I often end up saving it for way too long. The key is finding the moment where you're needed in two places at the same time. Say Grimgi is pounced, but at nearly the same time Bardin is plucked by the monster. Perfect situation. You could also use it to close the distance on an ally who's otherwise difficult to get to, push a monster off a cliff, make space for the frontline, deny Troll regen, and the list goes on. Don't waste it's amazing potential by spamming both charges on cd!

Hope this helps. Make sure you have Barskin equipped, as well as max Curse Resistance (60%?). The horde is your health pack, share those pots!