You may use this mod in a modpack as long as you do not make money off of it (Adf.ly, exclusive access from donations, etc.), you give credit (Linking back to this thread), you do not make any changes to the mod aside from config files, and you follow all of the other terms listed in the license below.
Tough As Nails is a survival mod that aims to increase difficulty through realistic features such as thirst and body temperature. There are other features that tie into it as well, like a seasons system with changing grass/foliage colors, temperature shifting for snow in biomes that don't normally get any, and more.
Check out the official Tough As Nails wiki for more information about the mod, crafting recipes, and more!
Body Temperature: http://i.imgur.com/7F9X3vT.gif
Lowered Starting Health: http://i.imgur.com/Pz09Tvd.gif
We have a Discord server! You can join with the following invite link: https://discord.gg/0loJvLMgvZi0q596