The Grounded Mantis - specifically the Orchid Mantis - is a late-game boss fight found inside the potted plant on the Shed porch, North of the BBQ. The Orchid Mantis is probably the toughest opponent ...

And of course, it all comes down to a fight. This seems fitting for the ending of Mantis, which is about the battle for leadership of the complex assassin underworld introduced in Kill Boksoon.