Hot Potato

Hot Potato is challenge #42. The goal is to defeat Satan. This challenge is unlocked by unlocking Tainted Forgotten.

The player starts as a blindfolded Tainted Forgotten. The Forgotten explodes roughly every 2.5 seconds, capable of dealing friendly damage to The Soul.

Strategy

 * While it requires a lot of patience, a viable strategy is to restart until a Mini-Boss Room with Lust is encountered and that it drops . It will dramatically increase the amount of contact damage inflicted when throwing The Forgotten, making it much easier to attack quick or regenerative enemies. As a weaker alternative, obtaining from a Boss Room will work as well.
 * While it does require some luck, visiting shops so you get Birthright and Car Battery can give you invincibility in rooms while leading the bomb to enemies. Similarly, using The Battery (mash Q as soon as you throw the skeleton to achieve invincibility) can mean permanent invincibility, at the cost of avoiding the skeletal form and making sure to press Q again once the bar is filled.
 * It's recommended to visit as many Curse Rooms as possible. Tainted Forgotten can enter and exit them without taking any damage, and they can provide precious soul heart health and powerful items such as and.
 * It's also beneficial to bomb any Blue or Purple Fire Places the player comes across to gain as much soul heart health as possible.
 * The Forgotten will move slightly every time it explodes, unless the character has an item that grants flight. Using could prove useful for keeping The Forgotten in one spot for a room.
 * Picking up is an instant win, as just holding Tainted Forgotten will provide permanent invincibility and free reign over where explosions occur.
 * Items that provide invincibility (such as ) or invulnerability to explosions (such as and ) are very powerful in this challenge, especially when combined with orbitals such as . Not only do they nullify self damage, they allow Tainted Soul to safely carry Tainted Forgotten as it is exploding, greatly increasing the player's control over where explosions occur. Take caution if there isn't full invincibility, though, since Tainted Forgotten's explosions can still push Tainted Soul while being carried, which could push them into enemies that survive the explosion.
 * Room clearing items such as and  can be useful for skipping rooms that would otherwise be difficult with Tainted Forgotten's mechanics, such as rooms with lots of fast enemies. In addition,  will trigger every time Tainted Soul takes damage, providing a good room clearing effect for the later stages of the challenge, though this should not be relied on too much due to the health cost.
 * The timer for The Forgotten's explosion resets every time a consumable is picked up or an active item is used. This can be used to avoid taking damage in certain situations. Items such as, , , and can be used to infinitely reset the explosion timer.
 * Since some bomb modifiers affect The Forgotten's explosions, playing the Bomb Bum can be quite powerful. Getting, , , or can be quite helpful as it will greatly boost the damage inflicted by The Forgotten's explosions.  will be triggered with The Forgotten's explosions, allowing to generate infinite pickups. , though, while boosting the damage, will also make dodging the explosions more difficult.
 * It is better to avoid . This item can help a lot if fighting small enemies, but if you encounter the Brownie boss, unless you can one-shot him, you will heal him with butt bombs instead. This can cause a soft lock.
 * Visiting all libraries is recommended as a will grant a lot of soul hearts and ensure that Super Meat Boy / Super Bandage Girl is obtained, which will provide the means to do damage to enemies without using The Forgotten.
 * It may be good to skip the Devil Room on the second floor to ensure an Angel Room spawns on future floors due to Tainted Forgotten being a character that can't get heart containers, making devil deals inconvenient. This will also maximize the chances of finding, an extremely powerful item for this challenge. On the other hand, the Devil Room can occasionally provide black hearts as well as , which is also very powerful in this challenge due to its invincibility.
 * It is also recommended to avoid items that revive the player as a different character (such as ), as upon revival the player will die immediately.
 * can be used to stall the explosions of the forgotten, as the forgotten will not move and will not explode during the jump animation. Gaining flight is not advised, as it will prevent the use of How to Jump, despite regularly being useable by characters with flight.
 * Using will allow The Forgotten to do a melee attack. This also works as it's thrown, functioning similarly to Tainted Forgotten's regular melee attack, but without the charge attack. It also allows you to delay the explosion, as each time you use it, the explosion timer will reset.
 * will allow The Forgotten to do a ring attack
 * will give the familiar to The Forgotten, granting you another way to deal damage more easily.
 * Urn of Souls stalls the explosion indefinitely by spamming the use button to activate and deactivate.