Does Sett Kingpin's ability that references 'my battlefield' apply when he is attacking a battlefield, or only when he controls the battlefield?

Ruling: 'My battlefield' refers to the battlefield Sett Kingpin is currently at. The ability is passive and applies while he is at a battlefield, including when attacking.

Nuances:

• The phrase 'my battlefield' means the battlefield the unit is currently at, not necessarily one the player controls