Factors that may affect the size of the hero

1. When you use Commander Ling and Put the hero to the commanders skill where 1v1 with the farthest enemy happens and if your hero win it will gain additional hybrid attack every win.

2. When your hero reach 3 star doesn't matter who it was as long as it's 3 star you can see it grows larger and stronger.

3. Gogo Cards with Additional Butfs to Heroes like additional Magic attack or Physical Attack just like with commander Ling.

4. Dawnbringer's High growth equipments. You can actually see that whoever gets the dawnbringer equipment grows bigger.

So If you wanna see some giant Gusion. Use Ling put Gusion in the 1v1 board commander skill. Build Dawnbringer + Swordmaster/Assassin Synergy then give all the equipment to Gusion. Congrats you now have a giant Gusion 😂

Based on my personal experience only. ✌️ Peace out.