Elder Geryon is one of the only boss that encountered once as the level boss of Mission 5.
With V this fight has no fixed pattern but, the less you get caught in slow sphere the better the fight is. Other than that the damage multiplier against this boss fluctuates due to the patterns and FPS. On the other hand, Vergil is very consistent with this fight. Because, he can stop Geryon's movement with Heavy Rain Blades
Devil Hunter is much harder because it lacks white orb where V can maximize the Nightmare summons with it.
Example 1 - Optimal fight start
Example 2 - Bad Skewer
Example 3 - Good RNG
NG+ is bit more consistent because it takes 2 good Domination to kill the boss :
New Game+ cycle
Compared to V, Vergil fight against this boss is scripted.
New Game cycle
New Game+ example
It's good to check the Frequently Asked Questions (FAQ) if you have general questions regarding the bosses.