Top: Lyα luminosity and maximum projected extension of HLock01-LAB compared to other Lyα nebula associated with type-II AGNs, QSOs, and HzRGs (see references in the text). Middle: relation between the total radio power and Lyα luminosity of nebulae associated with HzRGs (van Ojik et al. 1997) and type-II AGNs (Ao et al. 2017). The horizontal dashed line marks the approximate FIRST radio luminosity limit at z  ∼  3 (S_1.4 GHz  ∼  0.9 mJy). Bottom: line ratios of Lyα, C IV, and He II of several regions of HLock01-LAB. Other Lyα nebula associated with type-II AGNs (Dey et al. 2005; Prescott et al. 2009, 2013; Arrigoni Battaia et al. 2015b; Cai et al. 2017), QSOs (Borisova et al. 2016; Marino et al. 2019), and HzRGs (Villar-Martín et al. 2007a) are also shown. Detection limits of 2σ found in the literature have been converted to 3σ.