Barnshe sits atop Fort Windward, north of the Closed Bridges.
As you head north on your journey to meet Sophia, you will pass through the town of Arrisola. Just north are the Closed Bridges and Fort Windward. You'll be heading this way to progress through the main quest, so make sure your Temtem is near or in their XNUMXs before doing so. There is a mini-Temporium at the end of the Closed Bridges, so you can restock and heal there before heading to Windward Fort (and I recommend that you have at least ten TemCards on you).
Once in the fort, you need to head to the top. Progress normally, but don't be afraid to revert to Temporium as required. Eventually you will find yourself in front of stairs with daylight flowing: these lead to the top of the fort. If you plan to take on any opponents found before raising Barnshe, make sure your team is in great shape, around level twenty, and that you have balms and resurrect. I won't say why in this article for spoilers' sake, but you can thank me later.
Once at the top, just run and start random battles. The Barnshe is unlikely to spawn, so you might have to flee the fights if you want to keep yourself. The chances of a Barnshe appearing are not dire, but you will meet a lot of Ganki here. Once the Barnshe spawns, be careful not to shoot it down - it's immune to status effects, so sleep won't help. The best tactic is to use striking neutral attacks like Paharac's Peck to reduce it.
Just warning: it's to resist capture, so don't be discouraged if your Barnshe breaks free from your TemCards, even at low health. Just keep plugging in with cards until it gives way. Eventually, you'll capture the Barnshe and can head back south to finish off Denizen Icarus. That, and you'll have a fabulous obnoxious owl on your list.
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