Wukong is not exactly a useless champion but he hasn't been favoured by the meta for a while and Riot Games are trying to put a stop to the infamous streak. Come patch 10.2, Master Yi's pupil will sport some new mechanics and shifted numbers.
Riot Games are not too fond of the so called invisible bonuses. They are usually defined as the ones not giving enough visual or audio feedback while providing major buffs. This was the case with Wukong's passive, Stone Skin, that gave him more armour and magic resistance, depending how many enemies were around him. It is getting changed to a physical damage shield, visible on his health bar which will be equal to flat 12 per cent of Wukong's max health. It will only activate upon leaving a brush or stealth.
Wukong's Q, Wuju Strike, is only getting its numbers shifted. It will now have a lower cooldown but also deal much less damage since it will have only a 0.5 per cent bonus AD scaling instead of up to 1.4 total AD. Earlier ranks might be more useful for farming though as the mana cost will be reduced to 25. Bottom line, it will be a spammy ability with lower damage.
W ability has undergone major changes, including the name switch from Decoy to Warrior Trickster. It will still spawn a clone and make you invisible but only for one second instead one and a half. However, it will now be a targeted dash instead of a slight movement forward. Despite the dash's range of 350, you will not be able to jump over terrain with it. The clone will no longer be idle and will immediately start attacking enemies in range, prioritising the champions Wukong damaged. This also means you can spawn a clone next to an enemy and ult them to prevent them from escaping its damage.
Nimbus Strike (E) will remain the same for the most part. The only change is that it now deals magic damage even though it still scales with AD.
Cyclone (R) will have more consistent damage as the ticks will happen every 0.25 seconds instead of 0.5 but the tick damage will be halved to compensate. It applies Conqueror which means you can fully stack it up within 2.5 seconds while ulting a single target, without doing damage with anything else.
The movement speed bonus from Cyclone will now be a flat increase instead of winding up, Nimbus Strike's attack speed buff will keep refreshing while the ulti is up and the damage scaling has increased from 1.1 total AD per second to 1.25. Oh and it can be cancelled by casting other abilities or recasting Cyclone.