Do I need to challenge the Battle Institute and Subway for 100%ing Unova?

Question

Wanted to know if it is necessary to compete with the Battle Facilities in Unova to 100% the game...

Comments

There is no accepted set of conditions for 100%ing Pokemon, but maybe we can tell you some effects of using those modes that would be considered relevant e.g. Battle Subway is needed to get a trainer card star.

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As far as I know, 100%ing the game usually does mean getting every star on your trainer card, so please tell us if you mean something else

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Ok so the Subway should give me a star... I wanted to ask if there is any end to the Battle Institute like a final battle or something... Or is it just like the Subway where we can battle for infinite times

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I thought you can do only 5 battles at a time, and each set of 5 battles takes trainers and Pokemon from the same pool regardless of how many sets you've done before (and the game doesn't track win streaks).

Answer 1

You do need to challenge the Battle Subway to get a maximum level trainer card.
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In the Battle Institute, the "final battle" is simply the fifth one. Clearing multiple tests doesn't change the trainers or Pokemon that appear in each test.
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