For example, the formidable Robin Hood Champion of Sherwood became infamous when it debuted in Into the Inklands for having essentially the same ability, albeit limited only to when he banishes a character
Each single-player starter deck includes
Grand Arbiter Augustin IV Grand Arbiter Augustin IV consistently ranks among the saltiest commanders you can bring to a pod
The primary method is by challenging your opponents characters
Of course, the biggest upside of Zirda, the Dawnwaker is that its cost reduction applies to all permanents (see: the Basalt Monolith / Grim Monolith combos for Commander), and some artifact-based decks come very close to accidentally meeting Zirda, the Dawnwaker's companion restriction (for example, Modern Urza decks often only have Uro, Titan of Nature's Wrath as a permanent without an activated ability), so the unique wording on Zirda might open up new possibilities, compared to Biomancer's Familiar and Training Grounds, that will take time to explore