I am using Master Yi Wuju Master Legend. When I defend with Fiora Peerless, do I get the +2 from Yi first, then my Fiora ability procs going to 10 might, or does it do the double before and then apply the +2 might?

When defending with Fiora, Peerless while your Master Yi, Wuju Bladesman legend is active (and Fiora is defending alone), your Fiora will reach a total of 10 Might.

The calculation follows the game's layering and ability types:

Sequence of Events

1. Passive Application: Master Yi's bonus is a passive ability (it does not use the chain). As soon as the showdown begins and Fiora is designated as the lone defender, her base might of 3 receives the +2 bonus from Master Yi, resulting in 5 Might.
2. Triggered Ability: Fiora's "When I defend" ability is a triggered ability. It is placed onto the Initial Chain.
3. Resolution: When the Fiora trigger resolves from the chain, it doubles her current might. Since her current might is 5, it doubles to 10.

Why it works this way

• Layering: Passive bonuses that modify stats (like Master Yi's +2) are applied in the Arithmetic layer. Because Fiora's trigger is a "When" ability, it acts upon her current value at the time of resolution.
• Passive vs. Triggered: As confirmed in RiftJudge FAQ #9025, Master Yi's bonus is a continuous passive, not a trigger. It does not wait for a chain to resolve; it is active immediately upon the condition being met. Fiora's ability, however, is a trigger that doubles the current might. Since the +2 is already applied when her trigger resolves, the math correctly results in (3 + 2) × 2 = 10.

This interpretation is based on the constant application of passive abilities and the standard resolution order of the Initial Chain as defined in the Showdown Flow.