but he doesn't get +1 dice to cast and he doesn't have miscast protection, and he's realy expensive, also quite vunerable to cannons. same goes for our other monster characters, the rest are either have only somewhat usefull abilites, or cost a lot for the most part.
Chakax - he's something like 350+ points if I remember correctly, and he has a... 5+ ward... (not even a 4+, I mean come on, he costs more than a tooled-up khorne lord) and it works only in challenges (lol!), 3 or 4 S5 attacks.... how wonderful. His 'magic item / secret ideployment spying' abilities are kind of ok. Oxyotl.... is going to do what exactly? Doesn't he cost about 150 points? As far as I remember he shoots 2 BS5 S3 shots which are poisoned on 5+, and can snipe at characters. How exactly is that worth 150 points? Mazamundi - what disciplines doe she have? Soul of stone? So you mean that after spending 625 points on a Slann Lord I don't get loremaster, nor do I get +1 dice per casting, and he's now sitting on a combat monster which is vulnerable to cannons and is pretty much the last place he'd want to be. If he gave a 4+ ward to the stegadon he'd be considerably better, but I'd still never take him. He also suffers the ignomy of having a named magic item which does nothing - the shame! Kroq-Gar is one of the worst offenders in my opinion. I mean they gave him a named carnosaur mount which they could have given some unique special rules or a better statline, and they decided the best option would be to slightly alter the carnosaur's frenzy rule. GREAT. He's also HORRENDOUSLY expensive for someone who will be swatted aside by any cookie-cutter High Elf, Dark Elf, Chaos, Daemon, Vampire, Minotaur, Ogre, or Dwarf Lord.
I've often considered Oxyotl, but when I can get an entire unit of Cammo skinks for the same price, he goes right back in the box.
For just over 250 points Tetto'EKO is not a bad hero choice. I have used him numerous times Level 2 Lore Master Skink Priest, 5+ ward, sits in the 2nd rank of Skinks just like a Slann in TG, Can re-roll Comet arrival, Cosmic Events Special rule, I think he is worth the points.
mazdamundi can't join TG, no rumination, no cogitation, and he's a BSB without a magic banner, so good-bye Ld10. any unit that gets in contact with him can direct all his attacks against him, and even with his T and W ammount, unless heh as life he will die in 2 turns, andthen you're stuck wit ha steg. slann's weren't made to be pu on stegadons, and even if we had the option to put regular slann on stegadons i doubt many would chose it. tetto'eko seems fun indeed, barring the limited power dice 8th ed brought with itself. thehe-whatever is kinda nice for his points, you get a beast wizard that can be mounted on a steg for those who want something different from heavens but no slann... but no, don't use special characters, they are crap. demons are one of the few armies where special chracers are worth the points, and then some. even Archaon is allmost as good as a chaos lord of the same point cost, but can't get a dragon.
gor'rok is a solid hero choice IMO. for 215 points you get a very survivable hero who confers stubborn to his unit while adding an added punch. In my list he replaced my crown of command scar vet at -1 to hit him, immunity to killing blow, re-roll hits, and enemies reroll hits against him, I find him to be the most competitive of our heroes.