With the right equipment and Hero's Cores, Galio can become an immensely powerful force.
Factors that Make Galio a Strong Core
In recent patches, Riot Games has made noteworthy adjustments to Galio. In patch 13.3, the damage output from the Fist of Justice Core was increased from 75% to 150%. In patch 13.4, the shield strength from this champion's skills was enhanced.

These upgrades help Galio rise as an excellent 1-gold unit early in the game. Even top players from China have experimented with this unit as a core and achieved positive results. Galio's comprehensive offense-defense capabilities make it easy for players to snowball the match.

Constructing a Galio Core Formation
To construct this formation effectively, players need to own a 2-star Galio early on (after 3 rounds with the first monsters). Nasus should also be purchased at this point as he is a strong unit early in the game with a skill that slows attack speed. Additionally, units like Lee Sin, Gangplank, Malphite should be acquired to activate the 3 Superhero threshold.

Similar to other 1-gold 3-star upgraded team compositions, players should not purchase experience when using Galio as a core. Only after upgrading this unit to 3 stars should players start leveling up. Of course, when reaching level 6, purchasing experience should also stop to focus on upgrading Lee Sin, Malphite… to 3 stars.
For equipment, Giant's Belt and Guardian Angel are essential for Galio to effectively deal damage. Additionally, healing items like Hextech Gunblade or Hand of Justice are also good choices for Galio.

As for the Technology Cores, the Fist of Justice upgrade is indispensable. Upgrades like Heart, Vanguard's Edge are also extremely beneficial as their healing ability interacts very well with 3-star Galio (healing based on maximum health).
Conclusion
With beneficial adjustments from Riot, Galio can become an extremely strong core. If you need a change during the climbing process, a team composition centered around Galio is a very suitable choice.
