  We investigate possible factors that drive fast quasar outflows using a
sample of 39,249 quasars at median redshift $\langle z \rangle \approx$ 2.17.
Unique to this study, the quasar redshifts are re-measured based on the Mg II
emission line, allowing for exploration of unprecedented outflow velocities
(>6000 km/s) while maintaining statistical significance and uniformity. We
measure reliable C IV blueshifts for 1178 quasars with velocities >2500 km/s.
From those, 255(13) quasars have blueshifts above 4000(6000) km/s, with the
highest C IV velocity $\approx$ 7000 km/s. Several correlations are observed,
where higher C IV blueshifts in general are in quasars with broader, weaker C
IV emission profiles, weak He II emission, larger Eddington ratios, and bluer
UV continuum slope across the rest-frame UV to Near-IR. Analysis reveals two
primary factors contributing to faster outflows: higher Eddington ratios, and
softer far-UV continuum (h$\nu$ >24.6 eV). We find supporting evidence that
radiative line-driving may generate extreme outflow velocities, influenced by
multiple factors as suggested by the aforementioned correlations. This evidence
highlights the importance of considering a multi-dimensional parameter space in
future studies when analyzing large C IV blueshifts to determine the
fundamental causes of outflows.
