Trial of the Worm

Trial of the Worm is a player-vs-environment (PvE) game mode in Back 4 Blood. It has been announced on November 8, 2022 alongside the River of Blood expansion, which has been released on December 6, 2022. The game mode is available for all players and does not require an expansion to be accessed. Players can tackle the mode alone in Offline Mode or in a pre-made group, or find teammates via the matchmaking system.

Overview[]

Trial of the Worm can be either accessed via the player's menu or by interacting with General John Phillips/the other characters in Hope. This mode offers a four-player co-op experience that gives players a new type of challenge.

The mode plays almost identically to the Campaign mode in terms of content, so players will be familiar with the mechanics overall. Once a Mission has been started, it will be played as if it were in Campaign mode, with one difference being that while the six Hives would always have the Skull Totem Task, the regular Campaign Missions would always keep a Silence Is golden challenge. This means that if a team has selected, for example, the Resurgence Mission, the Cleaners will have to move from the Saferoom they started in to the destination Saferoom. Trial of the Worm features a gauntlet of four Missions, that players can run through to collect a Bonus of 75% more Supply Points over Recruit, just like the Veteran Difficulty. The default number of Fabulous Mementos is five and they can be increased by the Player Modifier Tree up to six to eight in total. Ugly Chachkies is the only inactive card in this mode, which would still be available to pick up at a Deck / randomly in Mission Intel boxes, but would have no effect.

Players will be able to apply Corruption Modifiers that will not only increase the replay value, but also the challenge that awaits them. There are Corruption Modifiers, grouped in four main categories, each of them having 15 points, i.e. 60 modifier points in total. The mode also features a score system alongside an online Leaderboard.

Players may use Burn Cards, but the Hell Can Wait card cannot be used, as no Continous will be available to them.
In addition, the Cleaners will have access to the Vendor in each Mission and the KSC Vendor Crates within Ridden Hives will feature all supplies that the regular vendor crates have to offer.

Completing Missions within the Trials of the Worm game mode will count towards the progression of Accomplishments that require a certain feature inside Campaign Missions to be completed, but will not count those Missions as accomplished, e.g. it will not mark Act 5 as completed in Nightmare/No Hope if those are done in Trial of the Worm, although secrets inside those would be available to find and achieve.

Score System[]

The mode features a score system, that allows players to compare with other Cleaners at Personal/Friends and Regional Score tables in the Leaderboards. To earn score points, players can complete Mission objectives or collect a new Memento type, dubbed Fabulous Memento. There are 5 Fabulous Mementos in each Mission by default, the number of which can be increased by spending points in the Player modifier category. The score multiplier can reach a maximum of x51., with the Horde, Ridden and Player max. bonus multipliers being x10, while the Difficulty's max. is x20. The base x1 adds to the score of up to x50 for the total of x1 to x51 .

Corruption Modifiers[]

The mode will offer four categories of modifications: Difficulty, Ridden, Horde, and Player. Each of these categories can be boosted up to 15x and grants an increased score multiplier. Players have 1 minute and 30 seconds to choose their preferred Corruption Modifiers. These modifiers can stack as for example the +5% Damage-modifier from the Ridden category can become a +15% Damage-modifier.

Difficulty[]

Players basically start at the lowest difficulty level, which is Recruit, but with each subsequent level the difficulty is gradually increased. While the usual Campaign Mode's Recruit, Veteran, Nightmare and No Hope are all implemented as their first rank (I), they can also be buffed to intermediate higher ranks, up to III. There is also a fifth difficulty - Legendary, that has four ranks, unlike the lower difficulties. It functions as a harder difficulty level than No Hope, with the differences of further lowering Trauma Resistance and increasing the Riddens Strength and Friendly Fire.

Rank	Modifier	Score Multiplier	Difficulty Settings
Rank 0	Recruit I	+0	Bonus Stats: NORMAL Trauma Resistance: HIGH Ridden Strength: NORMAL Event Difficulty: Normal Extra Lives: 1 Friendly Fire: NONE Roaming Bosses: 1
Rank 1	Recruit II	+0.15
Rank 2	Recruit III	+0.15
Rank 3	Veteran I	+0.75	Bonus Stats: LOW Trauma Resistance: NORMAL Ridden Strength: NORMAL Event Difficulty: NORMAL Extra Lives: 1 Friendly Fire: LOW Roaming Bosses: 1
Rank 4	Veteran II	+0.35
Rank 5	Veteran III	+0.35
Rank 6	Nightmare I	+1.5	Bonus Stats: NONE Trauma Resistance: LOW Ridden Strength: HIGH Event Difficulty: HARD Extra Lives: 1 Friendly Fire: HIGH Roaming Bosses: 1
Rank 7	Nightmare II	+0.75
Rank 8	Nightmare III	+0.75
Rank 9	No Hope I	+3	Bonus Stats: NONE Trauma Resistance: VERY LOW Ridden Strength: VERY HIGH Event Difficulty: VERY HARD Extra Lives: 0 Friendly Fire: VERY HIGH Roaming Bosses: 1
Rank 10	No Hope II	+1.25
Rank 11	No Hope III	+1.25
Rank 12	Legendary I	+4	Bonus Stats: NONE Trauma Resistance: LOWEST Ridden Strength: DANGEROUS Event Difficulty: VERY HARD Extra Lives: 0 Friendly Fire: DANGEROUS Roaming Bosses: 1
Rank 13	Legendary II	+1.5
Rank 14	Legendary III	+1.75
Rank 15	Legendary IV	+2.5

Ridden[]

The Ridden category offers a variety of ways to boost Common Ridden and Mutations. The following is a breakdown of the individual ranks and the individual modifiers per rank:

Rank	Modifier	Score Multiplier
Rank 1	+5% Damage	+0.1
Rank 2	+20% Mutation Melee Speed	+0.15
Rank 3	+10% Extra Slow from Common Attacks +1 Common Health Regen +15 Mutation Health Regen	+0.2
Rank 4	+15% Fire Resistance +15% Explosive Resistance	+0.25
Rank 5	+5% Damage +1 Corruption Card Difficulty	+0.3
Rank 6	Mutations recover from Stumble faster	+0.4
Rank 7	+10% Extra Slow from Common Attacks +1 Common Health Regen +15 Mutation Health Regen	+0.5
Rank 8	+15% Fire Resistance +15% Explosive Resistance	+0.6
Rank 9	+5% Damage +1 Corruption Card Difficulty	+0.7
Rank 10	+30% Mutation Melee Speed	+0.8
Rank 11	+10% Extra Slow from Common Attacks +1 Common Health Regen +15 Mutation Health Regen Common Attacks remove Max Health	+0.9
Rank 12	+15% Fire Resistance +15% Explosive Resistance	+1.05
Rank 13	Mutation Weakspot bonus removed	+1.2
Rank 14	Headshots Only on Common (Bullet & Melee hits on the body/limbs won't damage Common Ridden)	+1.35
Rank 15	+15% Damage MAX Corruption Card Difficulty	+1.5

At Rank 15, players will have to deal with the following 12 Ridden modifiers:

Modifier
+30% Damage
+50% Mutation Melee Speed
+30% Extra Slow from Common Attacks
+3 Common Health Regen
+45 Mutation Health Regen
+45% Fire Resistance
+45% Explosive Resistance
MAX Corruption Card Difficulty (3rd)
Mutations recover from Stumble faster
Common Attacks remove Max Health
Mutation Weakspot bonus removed
Headshots Only on Common (Bullet & Melee hits on the body/limbs won't damage and kill Common Ridden)

Horde[]

The Horde category offers, among other things, the possibility to increase the number of Common Ridden and Mutations and to strengthen Boss Mutations. These Horde modifiers are available between Rank 1 and 15:

Rank	Modifier	Score Multiplier
Rank 1	+5 Common per Horde	+0.1
Rank 2	+1 Mutation Variant(s) Level 1 Hazard Density	+0.15
Rank 3	+1 Common Variant(s)	+0.2
Rank 4	+10% Boss Health	+0.25
Rank 5	+5 Common per Horde Level 1 Boss Stun Resistance	+0.3
Rank 6	+1 Mutation Variant(s) Level 2 Hazard Density	+0.4
Rank 7	+1 Common Variant(s)	+0.5
Rank 8	Ferocious Bosses	+0.6
Rank 9	+5 Common per Horde Level 2 Boss Stun Resistance	+0.7
Rank 10	+1 Mutation Variant(s) Level 3 Hazard Density	+0.8
Rank 11	+1 Common Variant(s)	+0.9
Rank 12	Monstrous Bosses	+1.05
Rank 13	+5 Common per Horde MAX Boss Stun Resistance bonus removed	+1.2
Rank 14	+1 Mutation Variant(s) MAX Hazard Density	+1.35
Rank 15	Chance for +1 Roaming Boss	+1.5

The following 8 Horde modifiers will empower the Horde at maximum Rank:

Modifier
+20 Common per Horde
+4 Mutation Variant(s)
MAX Hazard Density
+3 Common Variant(s)
+10% Boss Health
MAX Boss Stun Resistance
Monstrous Bosses
Chance for +1 Roaming Boss

Player[]

The Player category, in addition to increasing the number of Fabulous Mementos, allows for a variety of negative modifications that limit the Cleaners' effectiveness.

Rank	Modifier	Score Multiplier
Rank 1	-10% Ammo Capacity +10% Vendor Prices	+0.1
Rank 2	-10% Sprint Efficiency -10% Move Speed while Firing	+0.15
Rank 3	+25% Environmental Damage taken +10% chance to spawn broken items	+0.2
Rank 4	-10% Ammo Capacity +10% Vendor Prices	+0.25
Rank 5	-10% Sprint Efficiency -10% Move Speed while Firing +1 Fabulous Memento(s)	+0.3
Rank 6	+25% Environmental Damage taken +10% chance to spawn broken items	+0.4
Rank 7	-10% Ammo Capacity +10% Vendor Prices	+0.5
Rank 8	-20% Sprint Efficiency -20% Move Speed while Firing	+0.6
Rank 9	+25% Environmental Damage taken +10% chance to spawn broken items	+0.7
Rank 10	+1 Fabulous Memento(s) -1 Team Extra Lives	+0.8
Rank 11	-10% Ammo Capacity +10% Vendor Prices	+0.9
Rank 12	-30% Sprint Efficiency -30% Move Speed while Firing	+1.05
Rank 13	+30% Vendor Prices +10% chance to spawn broken items	+1.2
Rank 14	No Friendly Cleaner Outlines Teammate Status shrouded	+1.35
Rank 15	+1 Fabulous Memento(s) -1 Team Extra Lives -1 All Accessory Slots	+1.5

On the highest settings, players will be affected by the following 11 modifiers:

Modifier
-40% Ammo Capacity
+70% Vendor Prices
-70% Sprint Efficiency
-70% Move Speed while Firing
+75% Environmental Damage taken
+40% chance to spawn broken items
+3 Fabulous Mementos (for a total of 8)
-2 Team Extra Lives
No Friendly Cleaner Outlines
Teammate Status shrouded
-1 All Accessory Slots

Corruption Cards[]

In addition to new cards, the Corruption Cards receive two new types: Boons and Curses. These additionally support or make it more difficult for the Cleaners to successfully complete a Mission in addition to the usual Corruption Cards.

In Trial of the Worm, all Corruption Cards have a level, which reflects the approximate beneficial or detrimental potency. The higher the level, the stronger the positive or negative impact of the card. Below is an example of three level variations of a card.

Boons[]

Boons are powerful enhancements for the Cleaners that increase their chances of successfully completing a Mission.
To keep the overview simple, variants of Boon cards have been omitted from the list.

Card Art	Title	Description
	Bonus Agility	Swap Speed, ADS Speed, and Reload Speed are increased by 25%
	Bonus Currency	Additional Copper spawns in the environment
	Bonus Damage	Damage dealt to Ridden is increased by 25%
	Bonus Intel	More Intel spawns in the environment
	Bonus Life And Revive Speed	All Cleaners receive 1 Extra Life and have 100% faster Revive Speed
	Bonus Max Ammo	Trauma Resistance is increased by 25%
	Bonus Trauma Resistance	Trauma Resistance is increased by 25%
	Flamethrower	A Flamethrower spawns in the Safe Room and additional Gas Cans are added to the environment
	Legendary Accessories	Legendary Accessories can be found in a Prepper Stash
	Legendary Attachments	Legendary Attachments can be found in a Prepper Stash
	Legendary Weapon	A Legendary Weapon can be found in a Prepper Stash
	Trauma Recovery	Instantly recover 25 Trauma

Curses[]

Curses are the polar opposite of Boons. These cards make it more difficult for the Cleaners to successfully complete Missions.
For clarity, variants of Curse cards have been excluded from the list.

Card Art	Title	Description
	ADS Disabled	ADS is disabled
	Extra Lives Reduced	Cleaners permanently lose an Extra Life
	Fast Bleed Out	Incap Bleed out Speed is increased by 25%
	Healing Reduced	Healing Efficiency is reduced by 12.5%
	Increased Incoming Damage	Incoming Damage is increased by 12.5%
	Instant Trauma	Cleaners receive Trauma Damage upon opening the Saferoom Door
	Loss Of Offensive Slot	Offensive Slots are reduced by 1
	Loss Of Quick Slot	Quick Slots are reduced by 1
	Loss Of Support Slot	Support Slots are reduced by 1
	Max Ammo Reduced	Max Ammo is reduced by 12.5%
	Max Health Reduced	Max Health is reduced by 12.5%
	No Copper	No Copper spawns in this Chapter
	No Extra Lives	Cleaners start with no Extra Lives
	Reduced Agility	Weapon Swap Speed, ADS Speed, and Reload Speed are reduced by 12.5%
	Reduced Mobility	Used Speed and Melee Speed are reduced by 12.5%, and Sprint Cost is increased by 12.5%
	Ridden Stumble Resistance	Ridden Stumble Resistance is increased by 12.5%
	Sprint Disabled	Sprint is disabled
	Stamina Reduced	Max Stamina and Stamina Regen are reduced by 12.5%
	Strong Locked Doors	Locked Doors are much harder to destroy
	Vendor Disabled	The Vendor is disabled
	Vendor Permanently Disabled	The Vendor is permanently disabled for the rest of this run

Mission Pool[]

At the start and between each Mission, players will be able to select one of three randomly selected Missions. The Mission Pool includes most Campaign Missions from Act 1 to 6, including the Ridden Hives.
Ridden Hives can only be accessed via a Mission selection and Hive entrances are disabled within all Missions. The Inner layer, The Nursery cannot be played in this mode. Players have 1 minute and 30 seconds to choose their preferred Mission.
Players who don't own DLCs and are without a player who owns the DLC expansions such as Tunnels of Terror, Children of the Worm, or River of Blood will randomly be able to access Missions of those expansions via this mode, although the final Mission of the game (Behold the Harbinger) is an exception as the players will be able to access ten out of the eleven non-Hive Missions, although all six Hives would randomly be optional. The Inner Lair (The Nursery) won't be accessible as it counts as a sub-hive, outside of the regular Hives. Additionally, there are three base game Missions, that are likely not among the optional Missions. These are: The Sound of Thunder, Heralds Of The Worm Part 1, and Act 4: The Abomination itself. This means Trial of The Worm grants access to of 46 of the 51 Missions.

Passing the Missions and Hives via this mode will not grant the Mission-completion achievements like for Recruit/Veteran in Act 5 or 6. Despite of this, some of the DLC accomplishments, like finding the Secrets in the Hives and Acts 5 and 6 will register.

Leaderboard[]

Players can access an online leaderboard by either interacting with the whiteboards in Kenny's tent or selecting it using the menu. The leaderboard offers a comparison between all players of a region and the filter option of how one's friends have performed so far.

The following information are displayed while looking at the leaderboard:
Name, System, Score, Multiplier, and Timed Played. In addition players will be able to jump to the top of the leaderboard and toggle through platforms via a keybinding.

Achievements[]

Trial of the Worm must be accessed in order to satisfy the unlock conditions for the following Achievements / Trophies:

Trivia[]

• On November 23, 2022, an individual responsible for managing the official Facebook account of Back 4 Blood posted the following comment:
  

However, it was later revealed that this statement from the official Back 4 Blood Facebook page was entirely inaccurate, as all the information in the article was, in fact, correct at the time. It appears probable that the user in question lacked access to the Trial of the Worm mode, leading to the dissemination of this erroneous statement.

Gallery[]