Both players can effectively draw as many cards as they want
III Until end of turn, another target creature you control gains trample and gets +X/+X, where X is the number of lands you control
To get two or three demons out typically isn't enough, especially when your opponents have a turn or two to prepare removal
Cursed Recording can give you a similar effect for more mana, but has a huge downside if you're casting multiple spells per turn
The use of contrasting reds and greens, the spikes and sawblades conveying a sense of terrible danger, and just the figurative image of someone fleeing while on a treadmill all combine to create a sense of dread that is perfectly captured by the title of the card
Being able to do this four times is incredible, and can lead to your battlefield being full of all of your opponents' strongest creatures