Build Son Goku (Youth)
Increases power of all attacks and all defenses by a tiny amount. Shortens skill cooldowns by a tiny amount.
Core Card

Lightning Swift: With this card and the movement given him by his passive Goku (Youth) can engage with a vanishing step and still be able to dodge/follow up for kills
Second Card

Art of Decoy: Boosts Son Goku (Youth) movement even further increasing his movement speed and reducing the cooldown of his vanishing step
Situational Cards

Steel Skin: This card is recommended against champions with DOT, or champions that will use principally rush attacks such as Super Saiyan 3 Son Goku, Toppo, Goku (Mini)
Third Card

Defense Step: This card reduces damage taken after a vanishing step, helpful for both engage and disengage
Situational Cards

Wicked Warrior: Boosts even further Goku (Youth) damage output with his rush attacks
Helper

Mr Satan: Follows you and launches a follow up attack against enemies hit by a rush attack.
Build Explanation
This Son Goku (Youth) build focuses on mobility, safe engages, and constantly keeping pressure on enemies without giving them an easy chance to punish him. His passive already gives him strong movement, and Lightning Swift pushes this even further, allowing Goku to engage with a vanishing step while still having enough mobility to dodge, reposition, or follow enemies trying to escape.
Art of Decoy makes this playstyle even more effective by increasing his movement speed and reducing the cooldown of his vanishing step. This gives Son Goku (Youth) more freedom to move around the fight, poke from a safe position, and quickly switch between engaging and disengaging depending on the situation.
Defense Step completes the build by reducing the damage taken after using a vanishing step. It gives Goku extra safety when diving onto an enemy or escaping from dangerous situations, making his aggressive movement less risky.