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The Binding of Isaac: Rebirth’s co-op explained (there’s a ‘baby generator’)

The Binding of Isaac: Rebirth is developed by steadfast indie porters Nicalis.

The Binding of Isaac’s Rebirth remake rips the Zelda-like’s Flash underbelly from beneath it and replaces it with a new engine. That’ll mean new 16-bit graphics, everything from the original game’s Wrath of the Lamb expansion, and best of all, local co-op. Played by babies.

Co-op partners can drop directly into the game by picking up a connected controller while you’re playing on the keyboard (or a second controller if you’re using the first).

A container heart will be plucked from Isaac, and attached to a brand new second-player avatar: a baby.

“I had originally thought of them as isaacs imaginary friends,” wrote Isaac creator Edmund McMillen. “But calling them babies is just more fitting.”

Whenever the second player joins the game or respawns, their avatar is randomly picked from a “very large” list of babies: Spider Babies, Love Babies, Bloat Babies, Water Babies, Psy Babies – you know the sort of babies.

There are cosmetic differences between all of them – but also plenty of special abilities.

“But a 2nd player is OP as is! Doesn’t adding special babies make things even more of a walk in the park?”, asked McMillen, rhetorically. “Well much like pills, every special baby has a ‘cursed’ counterpart. so there is just as much of a chance in spawning a baby that will randomly spawn a troll bomb every 1-2 min as getting a baby that heals p1 when it dies.”

The second player hovers above the ground, and can’t pick up items. Instead, the effects of whatever items Isaac has at the time of spawning are also applied to the baby. Player 1 retains control of when items are used – but babies can take additional hearts from the first player at any point by pushing start. It’s safe to say, then, that a certain level of communication and trust is required.

The game will be rebalanced for co-op to ensure its traditional brutality remains.

The Binding of Isaac: Rebirth is in the works at Nicalis, with McMillen in a supervisory position. It’s going to be out sometime before Christmas. Do you think you’ll buy The Binding of Isaac? Again?