Devī Ekānaṃśā, ekavīrā(solitary, without Her brothers), in her two-handed form.
For an introductory note on her, this blog post may be helpful,and a certain article of Coutre that I can’t remember right now. [Edit:It is The Harivaṃśa,the Goddess Ekānaṃśā and the Iconography of the Vṛṣṇi triads.]