To unlock all of Gabriel's skills, you'll need a substantial amount of experience points. While simply playing through the game will net you a good amount, there are ways to farm experience more efficiently. Replaying missions on higher difficulties often yields more experience. Additionally, achieving 'S' ranks on missions provides a significant bonus. Focus on missions with large groups of easily defeated enemies, or those with specific enemy types that drop more experience. The 'Arena' challenges (unlocked later in the game) are also excellent for farming, as they pit you against waves of enemies. Remember that using Shadow Magic increases the experience gained from defeated enemies, so activate it before delivering the final blow to a large group or a powerful foe. smash every destructible object, as they often contain small experience gems.
