Hatris (Arcade)

Hatris
Developer(s)	Video System Co., Ltd.
Publisher(s)	Video System Co., Ltd.
Platform(s)	Arcade
Release	WW: 1990
Gameplay info
Next pieces	1
Playfield size	6 × 32
Hard drop	Yes

Gameplay

See also: Hatris series gameplay overview

Rather than an instant hard drop, pressing Down on the joystick puts the active hat(s) into a "freefall" state. Hats cannot be moved left or right once put into freefall. However, hats in freefall may still be swapped by pressing the A button, and holding Left or Right on the joystick will buffer an instant movement of the remaining active hat or new pair upon leaving the freefall state.

Delayed AutoShift accelerates the longer the joystick direction is held. After an 11 frame start-up, the next shifts occur at 5 frames, 4 frames, 3 frames, 2 frames, and every 1 frame thereafter. DAS charge does not accumulate during freefall after pressing Down, nor during animations such as set clearing or fire burning, but will resume accumulation immediately afterwards.

Hat Types

Name	Score (Set Value)	First Set
Helmet	20	0
Bowler	40	0
Sombrero	50	0
Top Hat	100	0
Sorceror's Hat	150	10
Crown	200	15

There is a multiplier on hat scoring values that increases as the game progresses. Every 2nd speed change increases the hat score multiplier by one, up to a maximum of ten.

Fire

In addition to the six hats, there are also two types of fireballs that can appear as part of a piece pair. The standard red fireball burns the topmost hat set in the column it is placed. However, fireballs cannot burn crowns. Every eighth fireball has a 255/256 chance of being a special blue fireball, and a 1/256 chance of being a red fireball instead. Blue fireballs burn an entire column of hats. Blue fireballs are also extinguished upon reaching a crown in the column.

Each hat burned by fire is still worth points. The minimum value per hat is one-fifth the value of a set. As such, there is no scoring penalty for burning hats, aside from potentially passing up the opportunity to earn an additional 2x multiplier awarded for scoring a hatris.

Moreover, red fireballs in particular can score additional points depending on the number of hats in the stack. While a red fireball burning 1-3 hats is worth 0.2x per hat, burning 4 hats is worth the same as clearing a set normally. A red fireball burning a stack of 5 hats is worth 2, and burning a stack of 6+ hats follows the same rules as clearing such a set normally; see the relevant section below for details.

Sale

Every 15 sets of hats cleared, the Sale menu appears. The player is given the choice to remove all of one hat type from the playfield, or cancel and keep a Sale icon in stock for later use. No points are awarded for hats removed in this way.

If the player removes a hat type from the screen, that hat type will be marked as "Sold Out" on the next Sale screen and will be unavailable for selection; 150 sets of hats must be cleared after selecting a hat on the Sale screen before it will be made available for selection again.

Any unused Sales are represented by top hat icons below the "Sale" meter at the top of the screen. A maximum of six Sale icons can be stocked at a time. If the player has a Sale icon in stock, they can spend one by pressing the B button. Spending a Sale icon removes any actively controlled hats from the playfield, and brings up the Sale menu. As the Sale menu still includes the option to cancel without removing any hats from the screen, spending Sale icons can also be used to strategically skip unwanted pieces.

Bonus

If the cancelling of a Sale screen would award an icon in excess of the maximum stock of six, a score bonus is awarded instead. Bonus values start at 10,000 points, and increase by 10,000 points with each subsequent award up to a maximum of 60,000 points.

The Bonus value is reset if the player expends a Sale icon by pressing the B button. However, the player is allowed to make use of the Sale screen that appears after clearing 15 sets of hats without resetting the value (although naturally the current Sale Bonus will not be awarded in this case).

Clearing 6+ hat sets

Using the Sale system, it is possible to create sets of hats in the playfield that are larger than the normal size of five. Selling a type of hat that separates sets of another type of hat can result in an uncleared 5+ hat set remaining in the playfield. The player must add another hat to the oversized set to to clear it from the playfield.

Clearing a 6+ hat set awards a significant score multiplier. The multiplier is generally $Hats-1$ times the normal value. However, contrary to the scoring text, the special values of 11, 21, and 31 hats award 11x, 21x, and 31x respectively.

This score value is also still doubled by clearing a hatris. For instance, while a 5 hat set is worth 1x normally and 2x as a hatris, a 6 hat set is worth 5x normally or 10x as a hatris.

Randomization

The probability of receiving each hat is not equal. The odds of receiving each hat or a fireball are adjusted as the player makes progress through the game. The first two adjustments occur when introducing the Sorceror's Hat and Crown (at 10 sets and 15 sets respectively), and the final probability adjustment occurs at 51 sets.

Odds (out of 256)
Sets cleared	Helmet	Bowler	Sombrero	Top Hat	Wizard	Crown	Fire
0	28.12% (72)	25.78% (66)	23.83% (61)	21.09% (54)	0% (0)	0% (0)	1.17% (3)
10-14	23.05% (59)	21.88% (56)	19.92% (51)	17.97% (46)	15.23% (39)	0% (0)	1.95% (5)
15-50	19.92% (51)	17.97% (46)	17.97% (46)	15.23% (39)	14.06% (36)	10.94% (28)	3.91% (10)
51+	17.97% (46)	17.19% (44)	17.19% (44)	14.84% (38)	14.84% (38)	12.11% (31)	5.86% (15)

In addition to the individual probabilities, there is also a slight protection against receiving a pair of the same hat type. If both hats are of the same type, there is a 179/256 (~70%) chance the game will make one attempt to roll for a new type for one of the hats. This leaves a 77/256 (~30%) chance that no attempt will be made to change a matching pair.

A pair cannot contain two fireballs. In the rare event that a Fire pair still exists after the re-roll step, one will be changed to a Top Hat instead.

Gravity

Gravity (1/n G)
Level	Value	Level	Value	Level	Value	Level	Value	Level	Value
0	16	11	5	22	7	33	4	44	2
1	15	12	4	23	5	34	3	45	1
2	14	13	3	24	4	35	2	46	4
3	13	14	13	25	3	36	9	47	4
4	12	15	11	26	10	37	7	48	3
5	11	16	9	27	8	38	5	49	3
6	10	17	7	28	6	39	3	50	2
7	9	18	5	29	4	40	1	51	2
8	8	19	3	30	2	41*	7	52	2
9	7	20	11	31	8	42	5	53	1
10	6	21	9	32	6	43	3	54	1

After speed level 54, the gravity loops back to speed level 41.

The speed level at the start of the game depends on the configuration of the "Hat Fall Velocity" DIP switch setting.

Difficulty	Start Level
Easy	0
Normal	14
Hard	26
Super	36