Tags: ethereum blockchain crypto 

Rating:

TL;DR the password was visible on the blockchain using the `getStorageAt` method.
You could then change the owner and set the seed at your leisure.
The exploit from level 2 also worked.

[Read More](https://github.com/pietroferretti/ctf/tree/master/secconquals2018/gacha)

Original writeup (https://github.com/pietroferretti/ctf/tree/master/secconquals2018/gacha).