Black Luster Soldier also cannot be destroyed in battle
However, abilities often matter more
It also nullifies your opponent's graveyard - pretty backbreaking for strategies like 'Dredge' that rely on the 'yard - and allows you to grab your opponent's best threat from the void and play it free of charge (Okay, at the cost of its own life, but it's a lowly two-drop, so who cares?) Paired with targeted discard cards like the popular Thoughtseize, Dauthi Voidwalker has the potential to be super scary
No King of the Swamp with Toad and Baronne You can play with or without Toad or Baronne
In the early parts of of the original manga and anime, Machine monsters inherently had the special ability of being immunite against all type of magic, including attacks from magic users
This is probably because it's part of a very distinctive archetype and has a somewhat unique color combination, which means unusual cards that were very cheap beforehand now have a niche