I finally solved this! Diabolical. Here's a ROT13 walkthrough that covers the big steps.
Fgrc bar: pbzcyrgr yriry sbhe. Gur gevpx vf gb erghea gb yriry bar, frg tenivgl cbvagvat hcjneq, naq gura rkvg gur yriry. Jura lbh punatr tenivgl va yriry sbhe, lbhe thl va yriry bar zbirf gb gur evtug naq uvgf gur tenivgl obk qbja, nyybjvat lbh gb svavfu yriry sbhe.
Fgrc gjb: fxvccrq sbe abj.
Fgrc guerr: trg zhygvtenivgl cbvagvat hc naq gb gur evtug. Gb trg zhygvtenivgl, lbh arrq gb uvg gur tenivgl obkrf va gjb qvssrerag yriryf fvzhygnarbhfyl. Lbh trg guvf gb jbex ol cbfvgvbavat lbhe thlf va yriryf frira naq rvtug pbeerpgyl, naq gura haybpxvat gurz obgu ol svavfuvat yriry fvk.
Fgrc sbhe: bapr lbh unir zhygvtenivgl, jura lbh erfrg yriry fvk, lbhe thl fgnlf va gur pragre fdhner. Lbh jnag gb cbvag tenivgl hc naq hfr guvf yriry'f tenivgl obk sbe gur svany fgrc. Gurer'f bayl bar bgure yriry jurer lbhe thl pna snyy gjb fdhnerf hcjneq, naq vg'f n fhecevfvat bar: yriry gjb.
Fgrc gjb: gur zbfg fhecevfvat zrpunavp vf gung lbh pna ybpx yriry gjb ol uvggvat vgf tenivgl obk, fb lbhe thl trgf sebmra va gur zvqqyr ertvba vafgrnq bs ng gur ortvaavat be gur raq. Gb qb guvf, lbh arrq gb svavfu yriry bar, erfrg yriry guerr, naq cbfvgvba lbhe thl va yriry frira va gur yvggyr nypbir va gur hccre evtug. Jura lbh uvg gur tenivgl obk, gur punva ernpgvba zbirf lbhe thl va yriry bar bss gur raq fdhner, ybpxvat yriry gjb.
Nsgre lbh qb guvf, qb fgrc guerr gb trg zhygvtenivgl, naq gura cbfvgvba lbhe thl va yriry gjb gjb fdhnerf orybj gur tenivgl obk. Xrrc yriryf gjb naq fvk haybpxrq, frg tenivgl cbvagvat hcjneq, naq lbh'er qbar.