This bot is safe. Of course you can analyze it with any antivirus. It's just a Java program that simulates a real user playing with the site (no javascript, no hacks).

It doesn't resolve captcha. If you want to use it for auto-claim, you need to disable captcha from your account (this can be done by making a deposit, or wagering).

The safest way of earning BTC in freebitcoin is to use it as a saving wallet (it gives you 4% yearly, compounded DAILY), and use the auto-roll to win free satoshis every hour. This will give you profits 100% secure, with no risks.

Then, if you want to use the multiply BTC, we suggest to find a safe strategy and don't be greedy. Set a daily goal, and play until you reach it.

With the bot, you can do these things automatically...