Do D&D and Magic The Gathering staff help each other?

If a player attempts an ability check and fails, can they try again?

With Barbarian Rage, if they were to take 1 damage, would it reduce to zero?

What would be a good 3 hr adventure to run for my workmates?

You can download Mine of Madness here:
www.dmsguild.com/product/170811/Mines-of-Madness-Next?affiliate_id=237976
Screen Shot 2016-01-25 at 12.58.12