From LSWiki

Class: Athletic Skills
Attribute: Agility
Pedagogy: Physical Training
Practitioner Term: Tumbler

The ability to perform a variety of acrobatic tumbling maneuvers -- somersaults, cartwheels, handsprings, flips, rolls, vaults, and
so on.  This can be a significant aid to dodging attacks in combat.

Development Information: The tumbling skill was created by Chaos and is maintained by Lost Souls; the source code was last updated
Tue Mar 15 02:21:28 2016.

Trainers

Quetlatl: Itozuma Wanders
Losthaven: Raelan Jax
Shatterspire: Sthlar
Association required:
Brotherhood of Wine and Song: Danilo Thann
Maidens of the Spear:  Sulin
Guild required:
Hawkmen: Shayera
Nizari: Hasan Wanders
Quest required