Fallout Shelter has been a huge success for Bethesda. The free-to-play Vault management sim released on iOS devices three months ago, and since then, Android users have also joined in on the fun.

Now, a major update to Fallout Shelter may give players who have parted ways with their Vaults to return. Available now, the latest update to the game adds cloud saves so that you can pick up and play on multiple devices. That makes it more convenient to play than ever before, but a new difficulty level is the real reason players might want to consider coming back.

If you've mastered the art of Vault management and are looking for a challenge, the game's new survival difficulty is for you. Thankfully, gearing up your Vault dwellers will be easier than ever before due to the ability to loot Raiders. In addition to the new difficulty, Bethesda has also released a new legendary dweller in the form of Piper, who will also appear in Fallout 4. The developer is teasing the appearance of the Mysterious Stranger as well. Find him, and you'll be granted a bottle cap bonus.

All this comes just weeks before the release of Fallout 4, one of the most anticipated games of the year. Bethesda unveiled a new live-action trailer for the game earlier today that perfectly captures the tone of the franchise, and they released yet another look at one of the game's core character stats earlier this week. If you want to learn more about the stats and perk systems at play in Fallout 4, be sure to read this breakdown.

Fallout 4 releases on Nov. 10 for Xbox One, PlayStation 4 and PC.

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