This Modpack is needed to play TailsSMP — A server full of tech and QOL mods.
These include mods like
Create (And addons) : Adds machinery and automation to Minecraft
Project Red (And it's major addons): Adds Redstone improvements, with things like logic gates
Aeronautics: Adds Airships and physics objects to Minecraft
Civillis: Makes it so mobs spawn less in Civilized areas.
Sophisticated Backpacks: Adds Backpacks for inventory management
And much more misc and performance mods.
These allow you to do much more in Minecraft, and is a great modpack for Create even if you aren't going on TailsSMP.