Best mod of Minecraft?

I need some mods to my Minecraft server. Please, give me links. Thanks for understund.

The best single mod is IndustrialCraft 2. But I prefer playing a modpack such as FTB Ultimate Reloaded.

FTB mod packs, they're so good and their devs are so kind xd

This is a magic + energy mod. Very cool mods. I advise everyone to download

I think that FTB Ultimate Reloaded would be a good modpack!

Botania and Draconic Evolution with RF or AE2 is a must for any modded server.

IndustrialCraft 2. It could be confusing for newbies, but it has many great stuff like quantum armor

I've always loved Orespawn. A great mod combining new creatures, dimensions, ores, structures and items.

OpenComputers is one of the best mods imo. It involves programming but everything you'd do with redstone in a huge project can be done in a 3-block computer

SCP:Lockdown. It`s my opinion.
I like SCP foundation theme and this mod is perfect