Search its owners graveyard, hand, and library for all cards with the same name as that card and exile them
In Pioneer, Underworld Breach saw heavy play in Lotus Field Combo as it made the strategy unfair and consistent
Heres a table with these presumptions, and the two possible distributions
However, if you can boost his strength high enough that he wins skirmishes (generally using possessions, Noble Leaders (7R112) , The Last Alliance of Elves and Men (1R49) , or Merry, Friend to Sam (1R302) ), he can discard those minions for you, similar to the way he's used as ring-bearer
Most were very specific to one play style and werent particularly exciting
Even a tiny deviation in MTG card dimensions can disqualify you from a tournament or spell the difference between hundreds of dollars in resale value