"Killing on rails"

I really need tips on how to complete Toby’s lore challenge, killing on rails.
For those who don’t know what it is, you have to get 10 double kills (PVP only) with his ultimate ability, which is the core discharge which fires a huge beam dealing about 60 damage per second. It sounds simple, but it’s incredibly hard.
I have tried to make it easier for myself, on the level 10 helix I go for the upgrade that makes the core discharge slow enemies, and I have about +14% skill damage altogether, totalling core discharge’s damage to about 90 per second. I know that I can get one kill and then within about 6 seconds get a kill with the core discharge and that counts towards the challenge, but I still can’t get any kills with the discharge unless the enemy is on 25% health or less.

I just need to complete this lore challenge since the other one I haven’t done is fairly easy.
Any tips would really help. ex. gear loadouts, tactics etc.

Thanks guys

I think most people still outrun toby when slowed while discharge is going. I’ve had better results killing players with the lv 10 helix that breaks it into 3 shots.

I have read that only the SECOND kill of the double-kill needs to be done with core discharge. You can get the first kill with Toby’s railgun. I wish you luck; i’ve given up on that challenge, now that everyone still playing is pretty much a veteran player, and knows how to counter or avoid Toby’s lackluster ultimate.

…What a bummer.
I’m leveling Toby now and am here for this Lore thing and then read all these comments.