Play The Binding of Isaac as a Rotwood hunter fighting with Rotwood's hammer, played the way it plays in Rotwood.
The Rotwood Hunter: a new character on Isaac's character select. A canine hunter in Rotwood's starter armour, drawn with Rotwood's own idle, run and roll animations. Starts with the Forgotten's damage.
Rotwood's hammer moves: the timing, lunges, hitboxes, damage, hitstun and combo windows are read from Rotwood's own hammer.
Light (X / J / left mouse): the 3-hit combo, with Rotwood's swoosh arcs.
Heavy (Y / K / right mouse): tap for the jump smash, or hold to charge the overhead slam through three charge levels. A full charge also sends out a shockwave.
Dodge (A / Space): Rotwood's roll with its invincibility frames. It cancels attacks where Rotwood allows, and attacking out of a roll does a rolling attack.
Skill (B / Left Shift): uses your Isaac active item. The right stick or arrow keys also swing, Isaac-style.
Isaac items still count: speed ups make you run faster, tears ups make you swing faster, damage ups hit harder and reach further, Technology fires lasers, Brimstone fires beams from your smashes, and tear effects burst out of every slam.
13 Rotwood Powers (Frost Strike, Static Charge, Post-Kill Zoomies, Deus Ex and more) turn up in treasure rooms, boss rooms and shops, with Rotwood's names, icons and descriptions.
Single player. Plays with a controller, or keyboard and mouse.
You need The Binding of Isaac: Rebirth with Repentance+, and Rotwood. Nothing from either game is included: on first launch the mashup reads the hunter's art, the hammer's moves and the Power text from your own copy of Rotwood.