Glivedive Duo is a good example: a Bat/Lizard whose enters the battlefield ability also makes it effective in the different animal archetypes (as well see below)
You could choose one and spare most of your creatures while surely removing most, if not all, of the creatures on opposing battlefields
Theyre just cheap 5ban full arts with energy bubbles
For decks with three or more colors, where you might only be able to afford a small number of MDFCs since you'll need most of your lands to either be basics (for ramping / tutoring purposes) or tap for multiple colors of mana, the best MDFCs are Bala Ged Recovery (seriously, if you have green mana in your deck, play this card), Valakut Awakening, Hagra Mauling, and Ondu Inversion, along with the mythic cycle, which is almost always good if you can afford another land that only taps for a single color of mana
Protecting Krenko, Mob Boss is paramount to this deck's strategy, as is filling out the rest of the deck with cheap Goblin threats and payoffs that make them much more than 1/1 threats