Only really suitable for an "action"-related game, but it's certainly a way to think about what defines your character.
The Action Figure Test at the ghost of quarterbin.net laid it out for comics characters ten years ago, emphasising their visual appeal and presuming a limited number of clearly relevant accessories in a box or card.
Since then we've seen a widening of live-action-based figures from the obviously toy-friendly Star Wars and Star Trek to the plainclothes stars of Buffy and Doctor Who as well as their monsters (insert grumbling about lack of Rory figure here) among other things (both Sherlock Holmes and Hannibal Lecter have reached geek store pegs) and also an increase in accessorisation, especially in the big-ticket larger figures.
By way of example, what got me thinking about it this week is Big Chief's version of Amy Pond who comes with (among other things) different hands, some of her childhood toys, a mobile phone, a marker pen on a lanyard which she presumably had during the opening two-parter in 2011, and an apple with a smiley face cut into it. Compare to the standard Character Options version who comes with, er, nothing.
Of course, I've already considered this in the case of The Watch House: 1 2 3 4 5
And also miniatures, of course. Like so. And so. Even though we only used maps twice in seven years.
So what would you character need in a standard toy shop release, and what limited-edition extras would they have in a premium format boxed set?