Endless mode: entry, leaving with the Escape card, and stage 20

Endless mode unlocks after you beat the Witch. Enter through the floor hatch in front of the Church pulpit; each entry costs 1 Stamp. Inside, you fight waves in arena stages and pick a card at every level-up. The Amulet does not work, so the only ways out are dying or drawing the Escape card. Enemies drop no ammo; ammo comes from cards.

How a stage works

• Waves of enemies attack. Kills drop XP shards; collecting them levels you up and offers a choice of cards.
• After 8 to 10 waves a weakened boss appears. Killing it ends the stage.
• Since 1.0, remaining enemies are outlined if nothing dies for 30 seconds, stuck enemies return to their spawn, and uncollected XP shards vanish at the end of a stage.
• You can save and quit between stages.
• Library Cards and the Crown boost gun XP, not Endless XP.

Cards

Type	Examples
Items	A named item, three items, a random weapon, wearable, oil, scroll or trinket, 500 of an ammo type
Summons	Common, weapon or gear chest; a cooking station; one of your own storage units or service stations; a vendor; one or five tough allies
Run buffs	+50% ammo gain, +10 max health, +10% movement speed, +10% XP, +2 shard pull range, 25% thorns
Stage buffs	Double damage, +100% melee damage, double melee XP, full health, repair everything, no durability loss or no ammo use for 3 waves
Escape	Travel back to the Church alive. Cannot be banished

Because the “your storage” summon can bring your Church chests into the stage, spread spare potions and repair items across several containers before you enter.

Arthur’s Endless upgrades

Arthur sells Endless upgrades for Stamps: more cards per level-up (up to four), rerolls and banishes. Rerolls dig for Escape when you want to leave; banishes remove card options you never want (players banish melee cards) for the rest of the run. Experienced players buy up to 12 rerolls and 10 banishes before a long run. Banishing 50 options in total unlocks Exorcist.

Guns for a long run

Durability per kill decides Endless, because enemies drop no ammo and repairs come from cards and your bags. The Russian stage-20 guide gives two ways to keep it low: a durable gun oiled to kill in one shot (6 durability per kill at five enchantments), or a strong gun with no oils at all (1 per shot). It warns against guns under 2,500 durability.

Role	Build	Endless reason
Ammo-free main gun	Infinite-ammo D4RT	Three ammo-saving oils reach 100%, so it never needs an ammo card; 1,200 shots from one repair
Waves	Explosive 12Ga Corpsemaker	Forty exploding pellets per shot; the Russian guide’s stage-20 main gun was an assault rifle chiselled to 12Ga with Explosions
Elites and stage bosses	.50 BMG Pierre-Fusil	1,480 per headshot for spike-ball knights and the weakened boss
Interrupts	A clean high-durability gun with only a Scroll of Surge and a durability oil	Electrocution interrupts enemy attacks; the scroll makes it 2 durability per shot, and High Grade Oil adds none

The Russian guide predates 1.0; its 12Ga gun now loses seven-eighths of each pellet’s explosion and needs projectile oils, as in our build. SCamp and the Russian guide both take the stage’s double-damage card first: it lasts the whole 8–10 waves and cuts ammo and durability use. Ally summon cards also save durability, since allies have far more health in Endless than in the story.

Gear for a long run

From firsthand stage-20 runs (8 to 10 hours):

• One gun per ammo type, so one empty reserve never leaves you unarmed, and guns with high durability (above 2,500). Durability-free oils are worth their slot.
• Instant Defibrillator: sets you to 100 health instead of dying, once. Players call it mandatory.
• Titanium Helmet for explosion resistance against self-detonating elites; Plate Carrier for armour (movement-speed cards cover its slowdown).
• Detective Pipe (time 15% slower) and the Loaded Die or a Four-Leaf Clover for better drops.
• Supplies on the Japanese stage-20 run: about 15 repair tools plus toilet paper and swabs, about 15 potions and about 30 buff drinks.

Achievements

Achievement	Requirement	Steam players
Therapy	Clear stage 1	5.7%
Medication	Clear stage 3	2.2%
Meditation	Clear stage 5	1.1%
Enlightenment	Clear stage 10	0.5%
Cult Leader	Clear stage 20	0.4%
Exorcist	Banish 50 options	0.9%

Some players have been sent into Endless before beating the game, after using the Amulet or extracting early. No patch up to 1.0.6 mentions a fix; Escape or death returns you to the Church.