Mass of Mysteries | Prismabasher | Twinflame Travelers

Cards

At the beginning of your combat phase,
Mass of Mysteries triggers twice due to
Twinflame Travelers, giving
Prismabasher myriad twice.
Declare
Mass of Mysteries (if able) and
Prismabasher as attackers, attacking the same opponent.
Prismabasher's myriad ability triggers four times due to
Twinflame Travelers.
Resolve a myriad trigger, creating a token copy of
Prismabasher attacking each other opponent.
When the
Prismabasher token(s) enter, they each trigger.
Resolve the first trigger, giving five creature you control +5/+5 until end of turn.
Repeat step 6 for any remaining trigger.
Repeat step 4 for the remaining myriad triggers.

If your commander is attacking, you can boost its power to 21 or higher, which will deal lethal commander damage to an opponent. It isn't required for opponents to not block your creatures, as all the
Prismabashers have trample, but it is recommended when possible. When distributing the stat increases, make sure to give the creatures attacking each opponent just enough to deal lethal damage (if able) to maximize the effect. The amount of damage dealt will scale the more opponents you have.