Thats the sound of Dina, Soul Steeper chipping away at your opponents life totals whenever you gain life
Izoni, Thousand-Eyed I expect Izoni, Thousand-Eyed to be a big part of the fascinating Golgari decks that I talked about earlier with Vraska, Golgari Queen
The combination of its +1 and -2 ability means that its hard to fight this card efficiently, and it gets better when you have graveyard synergies or discard incentives in play like Bandit's Talent
Helitrooper's last ability reduces only the amount of generic mana you pay for equip abilities that target Helitrooper
Once you've assembled plenty of Towns and other nonbasic lands, cast Omega, Heartless Evolution to turn the tides of battle
Game Changers tend to be powerful cards you should disclose that are in your deck