Does Trifarian War Camp (battlefield that gives +1 might to 4-might units) trigger Volibear (when you play a 5+ might unit) and/or Legend Fiora (when a unit becomes mighty)?

Ruling: Trifarian War Camp triggers Volibear but does not trigger Legend Fiora.

Sequence:

• When you play a 4-might unit to Trifarian War Camp, the battlefield's passive applies before the "play" trigger resolves
• The unit becomes 5 might before being considered "played"
• Volibear sees a 5-might unit being played and triggers
• Legend Fiora does not trigger because there is no moment where the unit transitions from non-mighty to mighty - it enters already at 5 might

Nuances:

• This is similar to how Shield works - passive battlefield effects apply before play triggers
• The unit never exists in play at 4 might, so it never "becomes" mighty for Fiora's purposes