That card is Pete, and hes a godsend for Sapphire/Steel, helping it fair better against just about every other deck out there, but especially against Ruby decks
You expand your hand to the graveyard with this fantastic insect
Caustic Caterpillar + Haywire Mite Creatures that have secondary functions are good to have, especially in Limited or low-level Constructed formats
Its a different format with different rules that interacts in varying ways with MTGs design fundamentals, so the 100-card Singleton-style deckbuilding really lets the format shine in the uniqueness of the decks that players can dream up and build
To the vast majority of people this wont be noticeable
More common are kinds that change a type based on flavor, like converting something to a vampire with New Blood, resurrecting a hero as an angel warrior with Ascent of the Worthy, cursing the greedy to become, um, walls with Aurification, or resurrecting cards as zombies with Dread Slaver