If you didn't know Steel Charge was once rank 10 at max, then DE realized this was too much so they brought it down to rank 5 at max. But what about the people who brought it rank 6 and above?
DE ran a Script to give 2 Legendary cores, able to max any mod no matter what the max rank or rarity, to every one who ranked Steel Charge to rank 6 or above, to compensate for their hard work.
Im not gonna rage, in fact im going to try to be as civil as possible. My steel charge was rank 5 when the script went live, and i was planning on bringing it to rank 6 today(sucks for me :( ), I just find it very unfair that all i had to do is spend 17 rare 5 cores to bring it from rank 0 to 6 and i would get 2 Legendary cores just for doing that.
One legendary core is equal to 396 rare 5's when used on a rare mod, but no you dont get one,
you get 2.
Invest 17 rare 5's into Steel Charge and you practically get 792 rare 5's for free, yep that's fair.
They could have gave 1 Legendary core for rank 8 and 2 Legendary cores for rank 9 and above, i think that seems a little more fair than giving the power to max 2 Rare mods from 0 to rank 10, from only spending 17 Rare 5 cores.