Shopkeeper (Boss)

Description
The Shopkeeper can be fought in the Shop of any World. She will become hostile after being dealt 100 damage or opening the Shop for 30 consecutive times. Note that the Shop reopens automatically after Spell Upgrade and this also adds to her "patience count".

While visually the peaceful Shopkeeper has thousands of HP, she technically has 100 HP -- Trisect deals only 33 damage, and additional damage over 100 is ignored before the battle begins.

When spared, the Shopkeeper will occasionally appear at the start of battle, throwing 6 Sera total on random tiles of the player's side of the field. She is the only character that may appear as support in Eden, also against Serif.

Upon killing the Shopkeeper, a dark shape flies at the player. This denotes the player receiving, which is used to complete the Genocide ending. In addition, you will be rewarded 3 separate Artifacts, and a choice between 3 Spells.

Strategy
While at first glance the Shopkeeper appears to be a very difficult boss, with her large amounts of and high speed attacks, she becomes manageable with enough practice. The best way to learn to dodge her attacks is to simply keep fighting her as early as possible, as her attack patterns don't actually scale with her tier. Her attacks appear chaotic at first, but they can generally be dodged the same way every time.

Alternatively, an extremely effective (and somewhat cheesy) way to defeat her is to simply use on her during the Ice Walls Trap attack: the massive damage the ice walls take during the attack is enough to instantly defeat her early on in a run (4662 damage, given you leave 7 ice walls intact). Seed 171874145 contains a  on the first hazard zone for a flawless clear with Reva.

Opener: Sera Throw

 * Opens up by throwing Sera on some tiles, similar to the Sera crystals.

Ice Walls Trap

 * 666 dmg strike, ? dmg from standing on ice pillar Summon
 * Covers the player's side of the field with Ice Pillars (20HP, decaying by 5 every second), except top-left center tile.
 * After a second, a big 3x3 marker appears, centered on said tile.
 * After 2 more seconds, the tiles are struck dealing massive damage.
 * To Dodge: Move to the top-left center tile, then destroy the two ice pillars in front of your character and rush to the front column.

Quadrant Strikes

 * 99 dmg per hit
 * Groups of diamonds consecutively strike quadrants on the player's side of the field.
 * Though the strikes seem random, this pattern is the same every time, striking each quadrant twice.
 * The pattern goes as such: Top-left > Bottom-Left > Top-right > Bottom-Right
 * Note that that the second strike on the bottom-left quadrant lags a bit, allowing a short period to pass through that quadrant.
 * To go into more detail in the exact pattern: Top-left > Top-left&Bottom-left > Top-rightx2 > Bottom-right&Bottom-left > Bottom-right&Repeat-Top-left
 * To Dodge: Move in the 4 center tiles in a clockwise manner, starting from the bottom right tile.

Quadrant Demo
A demo of how to move during this attack. (Note: Speed is not to scale.)

Push and Strike

 * Pushes the player character 2 spaces towards either the lower, upper, leftmost or rightmost part of the grid, then hitting the 2 rows/columns on said side with explosions dealing 100 damage each. This repeats 4 more times.

Creeping X Pattern

 * Diamonds strike in an “X” Shape, with the center being in front of the shopkeeper. This repeats several times, with the center (and thus, the entire X) moving one tile left each time, until the center reaches the left side of the grid. These deal 99 damage.

"Random" Tile Strikes

 * 99 damage per hit
 * At low health: To start off her second phase, Shopkeeper moves to the front row and starts spraying attacks in quadrants in a seemingly random pattern.
 * This pattern is only performed once.
 * To Dodge: There is a safe spot right in front of her.
 * Using or Relocation spells is extremely dangerous before this attack, as the safe spot may no longer be on the player's side of the field if the Shopkeeper is not in the front row.

Line Strikes

 * 8 consecutive lines of diamonds will move through the player's position at specific angles. Each line re-tracks the player's position as he/she dodges previous lines, so that the player must constantly move to dodge them all. Each line is angled 45 degrees counter-clockwise from the previous line. Line 1 starts directly above the player and moves straight down, Line 2 starts top-left and moves to the bottom-right of the player, Line 3 starts directly left of the player and moves straight right, and so on until Line 8 which moves from top-right to bottom-left. These deal 99 damage.

Exploding Shard Cage

 * Summons crystals in the 12 “outer” tiles of the player’s side of the grid, in either a clockwise or a counter-clockwise manner. These have 500 health and explode after 2.5 seconds, following the direction they spawned in, dealing 100 damage to themselves and the tiles surrounding them (note that these explosions don’t damage the other crystals).

Execution

 * Executes the player character by crushing them with an ATM machine, dropping Sera on the ground.

Trivia

 * The line "I can't believe you've done this" is a reference to a viral video of the same name posted on Jul 13, 2007.
 * The line "F" may be a reference to the "Press F to pay respect" Meme from Call of Duty: Advanced Warfare.