Complex sentence: In the "Day of Vengeance" miniseries, the Spectre easily overpowered Jakeem Thunder and his 5th dimension genie, Thunderbolt, but the Thunderbolt's power is limited by its master's ability to verbally frame a wish.
Split into simpler sentences: In the "Day of Vengeance" miniseries, the Spectre easily overpowered Jakeem Thunder and his 5th dimension genie, Thunderbolt. However, the Thunderbolt is limited by its master's ability to verbally frame a wish.