the forgotten items (and ideas to fix)
now there are a few forgotten items, the main ones i want to talk about though are
and maybe 
now for poachers knife, the issue is its never built, even though if gives you a 500 gold boost for 3 camp invades. Now the point of this item should stay as an invading item, but instead of being a temporary item, it could be changed to something with a little more of a permanent effect during the jungle laning phase. It could possibly be given more dmg to monsters in the enemy jungle, or a %extra gold earnt from enemy monsters, but its 1 time bonus of 500 gold towards a serrated doesnt seem impactful enough for players to buy it (post ur ideas in the comments)
now for this thing
, yeah, that thing, you probably dont even know what it is, its ohmwrecker, a tower diving item, the issue with this one is that its stats arent that good, and its cost makes it the item feel irrelevant by the time you get it. So maybe a cheaper early game alternative that can be used to not completely stop a tower, but make diving easier, my suggestion
1800 gold cost
200 hp
55 armour
10% cdr
5% movement speed
Unique Passive - 10% bonus movespeed when under an alive enemy turret, this bonus is double for 3 seconds when you take damage from a turret
Unique active - Diver. 25% of damage allies take from turrets is redirected to you for 6 seconds (no redirection when below 15% max hp). Turret shots that hit you directly deal 20% less damage (60 second cooldown)
a lower cost that doesnt stop a tower altogether but still gives a dive aspect to it but not good stats, but still cheap, this way its a reasonable cost item for supports and some junglers (sej, maokai) might take this.
Now what i find an issue with
is that most champs, even with 1 spell spam, do dmg with other spells making it less relevant, people like cass was the aim for this item but it wont save you from her E, only her poison from Q and W. Now to make it a slightly wider variety of anti magic spam item, i suggest
50 more hp, 10 less magic resist, and change its passive to
Taking magic damage from a champion reduces the magic damage that champion deals to you by 15% for 4 seconds after an 2 second delay (4 seconds start after the delay, the delay doesnt need to be waited again until the effect goes away from running out of time)
give me the thoughts on how you would fix these items and how you think my ideas went
EDIT (i forgot to include all good in the poll and i cant edit, if you think they were all good just say all good at the start of your comment )