Nerf/Remove Conqueror
It really does not feel good having 1000 of my hp being done in true damage as a tank by a carry that I could beat under normal circumstances in a slightly extended fight.
Add an actual cooldown to it and/or make it not activatable by hitting minions first and/or lower the true damage %. 1/5 of your damage late game, assuming you have 200 damage is 40 damage that's unavoidable aside from not getting hit. With extended fighters/high attack speed, that 40 damage means about ~5 hits within the 3 seconds (maybe faster?), with it starting shortly after again when it procs.