Gaining changeling or devoid works exactly how you would expect it to unless you've spent too much time looking at the Magic rules
Heres a quick rundown: Magic the Gathering (MtG) is a long running, collectable card game for two or more players
Animar and Riku are the second and fifth most popular Temur commanders, respectively, only knocked down by Miirym, Sentinel Wyrm
The real decision that impacts your play experience will be how many other slots you replace with mana rituals, cantrips and tutors but Ill leave that choice up to you
The final tweak, was to create an instant that had a fluid customizability: This card is interesting because it encourages a player to build a deck with either a variety of creature types or with creatures that can change their creature type (see Mistforms above)
Its impossible to evaluate this card without knowing what support it will have