What made Vlad such a popular ban

He's amazing in organized teams that can coordinate a teamfight.

So pro games but not soloq.

Everyone banning him is just folks copying LCS.

Like all reworks and new champ releases, people need time to adjust. Once players have had time to mess around figure it out, they can deem the real strength of the champ. Idk if you've played against new Vlad, but he's pretty obnoxious.

Look at bard. People thought he was straight up bad at first. Fast forward a month or two, and now a good Bard makes you want to drink bleach.

People realized you can rush Spirit Visage and get an auto-win vs. any AP champ.

People see his empowered Q and think that all of his Qs are like that.

He's pretty incredibly damn hard to kill solo.

What everyone else said, plus your team never buys anti-heal items like (or penetration items), so he is literally unkillable.

Because he is a beast midlane.

They buffed his burst-base damages thanks to empowered Q and his E having a max health ratio. Also, Riot buffed the amount of AP he gained for building health.

As a result, as Vlad, you can now build very quickly against AP while retaining high burst damages (thanks to empowered Q and E max health ratio) against squishy target while healing yourself like a madman.

Playing as Vlad against an AP midlaner, you just need to build to be unkillable while having enough damages to kill your opponent.

players were adapting to him really slowly so he seemed weaker than he actually was riot buffed him based on how he was performing and when players figured him out it ended up being really strong