The best dredge cards are Stinkweed Imp and Golgari Grave-Troll because they dredge so many cards, and Life from the Loam for its synergies
Lastly, Stadium Trainer cards are played in the middle of the arena and affect both you and your opponent
Cards like Savage Ventmaw (plus a mana dork), Grand Warlord Radha, or a ton of mana dorks convert this into easy infinite extra combats
On the other hand, if I wanted to wipe your board with Extinguish All Hope, your Summon: Bahamut laughes in my face
While Ratchet Bomb isnt a Modern staple, it does see play, often in colorless decks lacking removal options, as a Karn, the Great Creator tutor target or in mono-colored decks that cant easily power up Engineered Explosives as an answer to Urza's Saga tokens
(And the vast majority says very nice things.) 2) Thinking You know what, wouldn't it be cool if the game had blah? and then just adding blah to the game