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Pocket Monster TV was a version of Dare Da? (Who's this?) in Japan. It replaced the normal Dare Da? as a commercial break transition/eyecatch for the anime and started from EP192.
Pocket Monster TV replaced the Dare Da? kids' voices with a computerized voice, changed the background, and showed the featured Pokémon's number.
The background text reads:
Monster number changes every time
What number is this time?
So are we ready?
Here we go.