Lines are quoted from the official notes; buff/nerf tags are auto-classified from the numbers and can be wrong. Covers the 14 most recent Overwatch patches PatchMeter has fetched.
⇄adjustReworked from "[Defense Matrix] heals you for 30% of the damage it blocks" to "When you mitigate 150 damage with [Defense Matrix], heal yourself for 15% of that damage and all other allies within 6m for 25% of that damage".
⇄adjustChanged from "+50% [Call Mech] Radius. [Self-Destruct] explodes 15% faster" to "[Self-Destruct] explodes 25% faster and costs 50% less Ultimate Charge but deals 75% reduced damage and only grants 75% Ultimate Charge after detonation".
⇄adjustChanged from "During the first 2s of [Boosters], [Defense Matrix] recovers 125% faster" to "[Boosters] damage grants 0.5s [Booster] Duration and restores 5% [Defense Matrix] Resource and heals 5% Max Life".
⇄adjustNow scales from Max Life instead of Max Shields and Armor.
▼nerfScaling reduced to 15% (Down from 25%).
⇄adjustNow counts as [Boosters] damage.
▲buff"When you mitigate 150 damage with [Defense Matrix], deal 20% increased Weapon Damage for 3s".
✕removedRemoved.
⇄adjustReworked from Dae-Hyun's Detonator.
⇄adjustChanged from "If your [Mech] detonates while mid-air, increase [Self-Destruct] explosion damage and range by 100%" to "During [Self-Destruct], if your [Mech] detonates while mid-air or deals [Boosters] damage, [Self-Destruct] explodes 100% larger and causes enemies to take 50% more damage for 5s".
✕removedRemoved.
⇄adjustReworked from Busan Blaster.
⇄adjustChanged from "Ability: Use [Secondary Fire] while de-meched to fire an explosive piercing shot that deals 80 damage" to "While ejected from your [Mech], hold [Jump] to fly and hold [Secondary Fire] to fire an explosive shot that deals up to 80 damage and slows enemies by 30% for 3s".