I vote eyeliner!  I think it's me and @eshoe on this hill with @WinglessOne adjacent!  But that's ok!

Yes, you can use eyeshadow as liner, but it's not the same as a nice brush tip or the perfect felt.  I can't go without liner on these eyes of mine, and that's that!  

GXVE BY GWEN STEFANI Line It Up Clean 24-Hr Gel Pencil Waterproof Eyeliner Spiderwebs 

MAKE UP FOR EVER Artist Color Pencil Long-Lasting Lip Liner 708 Universal Earth 

NARS High-Pigment Longwear Eyeliner Via Veneto 

PAT McGRATH LABS PermaGel Eyeliner Pencil 

Fenty Beauty by Rihanna Flyliner Longwear Liquid Eyeliner 

Rare Beauty by Selena Gomez Perfect Strokes Matte Liquid Liner Black