A 400% deposit casino bonus is an enticing offer that significantly boosts your initial bankroll, allowing you to play more games and increase your chances of winning. For instance, if you deposit $100, the casino adds an additional $400, giving you a total of $500 to wager. This type of bonus is often designed to attract new players, providing them with ample opportunity to explore the casino's offerings. However, it's essential to read the terms and conditions, as wagering requirements and game restrictions may apply before you can withdraw any winnings.