[Akame]

Just a small adjustment to play nice with the GR.

Current:
Rank 1: +5 hit; Darkness damage: 2, ignores armor.
Rank 2: +10 hit; Darkness damage: 4, ignores armor.
Rank 3: +15 hit; Darkness damage: 6, ignores armor.
Rank 4: +20 hit; Darkness damage: 8, ignores armor.
Rank 5: +25 hit; Darkness damage: 10, ignores armor.

New:
Rank 1: +5 hit; 10% Dark ATK, ignores armor.
Rank 2: +10 hit; 20% Dark ATK, ignores armor.
Rank 3: +15 hit; 30% Dark ATK, ignores armor.
Rank 4: +20 hit; 40% Dark ATK, ignores armor.
Rank 5: +25 hit; 50% Dark ATK, ignores armor.