Arlo was the first Tsum Tsum in the Internal version of the game to be introduced and only available via a Pick-Up Capsule. Of course this makes it very difficult to raise his skill level since you have to use skill tickets. Because of this you would think it would either take less boxes per level OR he would be insanely awesome. Sadly neither are true and wouldn't suggest wasting skill tickets to increase his skill level.
His skill is interesting. After you activate it you draw a line on the screen and Arlo will follow the path you traced and spot will show up and mirror what Arlo is doing and clear Tsums as well. You don't want the mirrored path to cross the path you draw so we have found the best to be drawing something like half a heart. Start at the bottom center and draw diagonally towards the middle right before making a half circle up and towards the center. It takes some experimenation; however, honestly he isn't the best Tsum even with a high skill level and given how difficult it is to raise his skill... not worth it