Leon started the day with practicing the Mountain Lord Hammer Technique. It was an E-Rank technique humans had discovered in a small remnant village of Titans.
It allowed him to bring out the might of a Mountain Lord, who was also the Chieftain of that village, for a short moment.
His strength grew explosive, and he could deal twice his normal damage with the Hammer. It might be considered low-ranked for others, but it was very suitable for the current Leon.
But it did take a lot of practice and hard work to reach Stage 1 of its Mastery.
If one wondered about the difference between Techniques and Skills, then they would get a very simple answer.
None!
At the core, both Techniques and Skills were the same thing. The term "Technique" was just more commonly used for physical body-related Skills like his Iron Skin and now the Mountain Lord Hammer Technique.