15 май 2021, 23:0315.05.21
Channeler's skill has a longer cooldown than Apo's or High Khatun's (booked 4 vs. 3 on the others), making him less valuable in dungeons.
Apo and HK both have a much better aura.
Apo's heal making him great in dungeon content.
Channeler is just a worse version of Apo/HK. And as HK is free (log-in reward), nobody uses Channeler.