If a creature you control being dealt damage causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time
The creatures pretty small, but sneak makes it easy to get the first trigger and start doubling up on artifacts, whether that means a surge of mana from a second Relic of Sauron or two finishers like Portal to Phyrexia and Cityscape Leveler
You'll also get to make use of any enter-the-battlefield or death triggers those creatures feature (note, as Deadpool's ability is a replacement effect not a triggered ability, Deadpool enters with the text box he's stealing, so can copy ETBs)
You can cast a second copy of your instants and sorceries during your turn, which helps set up powerful combinations
Securing the Win Once you have all the cards that make your deck workattacking Pokmon, supporting Pokmon, and Trainer cardsyou can start to think about additional cards that boost your decks strengths or cover any weaknesses it might have