This is because you are playing new and old Eldrazi titan creatures with large amounts of colorless mana to get them online as fast as you can
Fittingly named, this card is the ultimate last-minute rescue plan
The intrigue and pull of Edge of Eternities is strong, go figure that landfall is a heavily supported archetype
While Im not sure if it truly makes the cut in cEDH, you could also cast Return the Favor to make your own copy of the enters-the-battlefield ability of Thassas Oracle to win on top of their ability on the stack
Against Aggro this card might just rot in your hand, and if your opponent can Burst Lightning their Screaming Nemesis so that you can't gain any more life, this card becomes even more useless
Additionally, its activated ability is unique in the sense that each piece of equipment can be used as a removal spell or as a way to deal direct damage to players