Save, replay, and challenge modes

The RPG elements extend to your secondary inventory. Each sub-weapon has a "standard" mode and a "Magic-infused" mode: Silver Knives:

: Landing consecutive hits without taking damage fills the Focus Meter. Once full, enemies drop Neutral Element Orbs upon being hit, which are essential for replenishing magic. The Magic System: Light and Shadow

Castlevania: Lords of Shadow , "RG" likely refers to the Mechanics VoiceOver (R.G. MVO)