I'm sorry to say but Lethality items are a joke
The only lethality item worth buying on an assassin type champ is yommus anything else is just trash. There are champs that like lethality but can't use it because the items suck. Dusk blade is tailored to a few champs plus a couple adcs since it relies on stealth while yommus can be used on any assassin because it's a good item design for ad assassins. Edge of night is a very poor item considering that most engages coming from assassin champs are predictable and if you hop into let's say a cait and she has 2 others by her the assassin is probably dead anyway the spell shield isn't much of a help since cait crits for more damage than the assassin will do anyway. Imho also lethality is not a very good concept it takes away what armor pen was all about. You can't even run a full lethality page like you used to be able to with armor pen because you lose so much damage its actually sad.