The Half-Venerable Dragon allowed Wang Yan to kill the Blazing Flame Flood Dragon because it had calculated that Wang Yan's Power of Demon Patterns was not infinite. Once it was exhausted, Wang Yan would be ripe for capture.
However, though Wang Yan's aura seemed weak, upon hearing the Half-Venerable Dragon's words, he burst into laughter. The laughter was so loud it overshadowed the Half-Venerable Dragon's own.
The Half-Venerable Dragon paused, furious, and demanded, "What are you laughing at?"
Wang Yan halted his laughter and replied, "I'm laughing at your shortsightedness. I don't have much else, but I do have plenty of elixirs. When my Power of Demon Patterns is depleted, I can replace it with elixirs."
Having said this, the Starlight Ring on Wang Yan's finger flashed, summoning an elixir that flew into his mouth.
Once the elixir was consumed, Wang Yan's previously weak aura immediately surged, returning to its former peak.
