The Hippus can also profit under good circumstances nicely from controlling counter(also not tested just thought up now):
Their hero Magnadine captures all barb units he defeats. If Magnadine is gotten early enough and leader is Tasunke(aggressive, raider->more xp for magnadine and 1fsc), Magnadine has str13(11+2 hero), combat 5(+100%

, formation 1(+40%), drill2(1-2 fs) and enchanted with dance of blades(1fs), he will bring against a rider 13*2.4=31.2 with 2-4 first strikes and is guranteed to convert him on victory.
Now the same anyone can attempt with inquisitors, their beaker requirement is similar, but they fail 50% of the time controlling, they are weak, so need other units for softening up(and maybe killing the rider instead).
The main advantage of Magnadine is, that he is terrible fast(mv 4 + commando), so will reach the rider in time before he dies or levels to much, if on same continent and that he levels fast, starting with combat 1 and getting +1 xp per battle.
But his levelling speed turns ridiculous if he gets all 3 flanking promotions and orthus axe, then he can attack 3-4 times a turn without risk and is guranteed to gain at least 1 xp(2 xp if below 100) per combat. (Also assuming he stays out of range of ring of fire and other direct damage stuff)
And if he needs something to soften a rider, he can go to any nearby city and get loyal(=fear resistant) mercs for 120 gp.
Getting 4 str 29 units with individual special stuff(command, plague carrier, wraith creating) would be a huge advantage.
Getting Avatar of Wrath seems more difficult, because he starts with lot of units(softening up difficult) and combat 3.