Naramon Shadow Step

[Lotus.slayer]

naramon set as main focus, pool 11/12, shadow step max , prisma dual cleavers whit critical build and naramon len,  warframe whitout any len , no other weapons and after using 5th ability and making crits whit melee i cant be invisible, how or why i tried almost everything. is it bugged?

[crazyN00b]

go to the focus tree, make sure shadow step is red (enabled) , not black (disabled). Click on shadow step if it's disabled.

[(PSN)Exi-Eni-Eli]

So, you couldn't receive the invisibility upgrade even after using your fifth ability?

Hm.... 

I'd just have to try what crazyN00b said, and make sure it is in fact "enabled".