The Bag of Preparation is a common relic that draws an additional 2 cards at the start of each combat. Its effect is identical to the Ring of the Snake, the Silent's default starting relic.
This relic is very powerful despite its rarity. Its effect synergizes with many other relics and cards, and the additional card draw increases the potency of your first turn. However, if you draw too many key cards and are unable to play them all, this relic could possibly set you back for a few turns.
Gambling Chip: You can mulligan additional cards drawn by Bag of Preparation.
Lantern and Ancient Tea Set: The extra Energy for the first turn along with additional card draw from Bag of Preparation greatly increases the impact of your first turn.
Mutagenic Strength: More Strength for your first turn in addition to the card draw makes your turn 1 attacks much more potent.
Ninja Scroll and Holy Water: The generated cards takes priority over Bag of Preparation, and could clog your hand as you cannot have more than 10 cards on your hand at a time, potentially rendering additional draw useless.
Ring of the Snake, the Silent's default starting relic.
Cloak Clasp: Gives additional protection at the end of your first turn, which is generally the turn in which you are most vulnerable.
Ring of the Snake, 
Ring of the Serpent, 
