Board Thread:Questions and Answers/@comment-43540932-20191129231109/@comment-28362353-20191130020117

Another thing to note is that there are ways to tell what boosts are multiplicative and which aren't.

For example, boosts such as support passives, passives with "+x% per x ally", etc., are all start of turn, and are additive on top of each other, not multiplied.

However, passive such as "when launching a super attack" or "after receiving an attack" or "with each attack performed/each attack received" are all during turn, and are separate from start of turn passives, and are therefore multiplicative. (This also includes DEF stacks from supers)

Xeno Vegeta is one of these cases, where his additional 50% when launching a super is separate from his start of turn boost of 100% (135% if he has his full 35% from allies), meaning its multiplicative, resulting in the 252% boost you see on the page.