When you have a companion in your deck, no matter if its best-of-one or best-of-three, itll occupy one of your sideboard slots the last one, to be more precise
However, because they aren't cards and won't stay in exile, any abilities that refer to what you "used to craft" the back faces won't refer to anything
While creatures from this plane have appeared in Magic before, this is the first time were visiting there properly
Anyway, solid enough especially because you get to draw off Treasures or Food or whatever
How you answer these questions will vary based on your playstyle and deck, so dont be afraid to experiment until you find a blend of mana ramp cards that works for you
Tymna the Weaver [Partner]: That is one awesome effect in a table with say, four opponents