This is the next chapter [Part IV) of the golden age Dr. Voodoo adventure serial "Quest For the Golden Flask", which I have available and is taken from Whiz Comics #20 (Aug. 1941); originally published by Fawcett and again featuring lovely artwork by Mac Raboy.
The character called "Nero" is specifically identified as Dr. Voodoo/Hal Carey's native companion in this story titled "The Queen of the Giants". The Catacombs is grateful to Don "Zu-Gogo" Falkos for providing the scans for this story. Note: The copyright for this issue, its contents and artwork belong to the original publisher and/or creators and is reproduced here solely for entertainment purposes.
Stay tuned for additional chapters of this serial down the pike, eventually. Enjoy!