It is all about the potential to do those big turns where you do multiple powerful things
Whichever ability you choose first resolves last when it comes to undying and persist
You want to get a big legend into your graveyard, reanimate it with the titular instant, and ride that huge value wave to victory
Inklings best fit in token decks that can pump or upgrade them with cards like Intangible Virtue or Divine Visitation, double them with cards like Mondrak, Glory Dominus or Thalisse, Reverent Medium, and bounce back from your board wipes like Hour of Reckoning faster than opponents
Special action cards deliver game-changing moments as they help you defeat your opponents
It makes a mercenary, but more importantly it copies abilities that commit crimes if they target your opponent or their stuff