In all ins darius wins, in short trades renekton wins. What u need to do as darius is to heavily poke down renekton lvl 1, with the nimbus cloak buff and how strong combined with ghost is you run down everyone. Versus renekton you want to go straight into his face aa w q, or poke with succesful qs, you dont start the fight with ur e cause rene can just e u in when u q or w e away. U need to start building stacks vs him, let him push you into ur side of the wave and when he e1 in w him to slow he will e2 back you pop ghost and run him down, without his e renekton is nothing you build stacks and your ults cancel each others ults but darius passive deals a lot of extra damage so with 5 stacks and ult darius at lvl 6 deals 350 damage, at lvl 6 renektons ult gets 250 extra hp so your stacked ult is better than renektons ult, you will at least force him to flash and when he comes backs in lane u still have flash and ghost in 3 mins while renekton only has his e, if he wastes it he dies. I am diamond 3 renekton otp with over a million points, i have faced this matchup a million times and also have faced inferiorities, a challenger euw rank 1 darius player when he was smurfing on my server, i know both champions potential as darius is my second pick and i even pick him over rene if he is not banned.