The tamed beast version of Vornas, The Fell Flame is missing any bonus modifiers.

So according to a list of tamed boss monster modifiers sent to Zizaran by GGG, Vornas and his map equivalents are supposed to have the following modifiers:

"all_damage_can_ignite 1

ignite_chance_+% 300

active_skill_ignite_effect_+%_final 100

active_skill_base_physical_damage_%_to_convert_to_fire 50"

I can confirm from experimenting with the version of Vornas from acts that the tamed beast version lacks these modifiers entirely. In addition to this, the tamed version of Vornas only uses basic attacks, none of its normal boss abilities