New item "Luden's Echo" experiment over it's already hilariously overpowered in its current design

Item 3285 (3100g) Needlessly Large Rod + Aether Wisp + 650g +120 Ability Power +7% Movement Speed UNIQUE Passive: Gain charges upon moving or casting. At 100 charges, the next spell hit expends all charges to deal 100 (+15% AP) bonus magic damage to up to 4 targets on hit.

I won't go into the AP lets first discuss the movement speed.

Movement speed is the best stat in the game for ranged period, there is not a single ranged champion in this game that doesn't want as much movement speed as possible, that's why everyone builds boots first, increasing every ranged casters movement speed by 7% all at once will break the game in half, it'll make poke mages even harder to catch, poke comps will be the norm, melee will be phased out even more and it'll just reinforce passive play when it makes it even harder to initiate on the back line.

lets now discuss this passive, i assume it'll charge just as fast as Statikk shiv, 10 charges per spell 5 charges per 100 units moved. First off giving an item like this to casters who are even further away than ADC's and even more safe is hilariously stupid, there is no way to zone them or lock them down preventing them from gaining the charges in a team fight, add this with poke mages and you essentially just create the perfect item for mages with poke, especially when you add the bonus damage. Late game we can assume this item will do about 160 damage a pop, once a class that builds magic penetration, essentially removing the actual weakness that statikk shiv does have, where a little bit of magic resist can mitigate the damage. With magic resist being nearly impossible to itemize as is and ADC's pumping out so much damage, this just adds even more damage being applied to tanks that cannot possibly be survived against.

The item itself seems to laugh in the face of melee bruisers and tanks, especially the low mobility ones, they'll never close another gap again and now the mages will be rewarded for actually kiting these champions, beyond the basic rewards of you know not dying and killing bruisers. Now they get even more damage and rewards for killing them and with the extra movement speed only the likes of Vi and Jarvan will really have to means of closing the gap and maybe locking down the mage long enough for people to catch up.