|Release Date(s)||April 13, 2016|
The gist of the gameplay is that time only moves as fast as the player character, a simplistic stick figure, does. That is, if the stick figure is not moving, the flow of time will be stopped as well; if the stick figure is walking at the normal rate, time will also flow normally; and if the stick figure is moving quickly, time may flow twice as fast.
The flow of time is referred to in the game as "timerate", measured in seconds per minute. Everything in a level except for the stick figure is affected by the timerate; the stick figure moves according to basic physics, falling toward the bottom of the touchscreen no matter the flow of time (although the act of falling does inherently affect time).
Importantly, the timerate caps at +120spm; this means the stick figure also has a cap on speed. A corollary to this is that the stick figure's velocity can cap itself via the timerate limit. For example, if the stick figure's overall speed exceeds twice the normal rate upon riding a moving platform, thus breaking the double-timerate limit, time will automatically slow itself to a rate where the stick figure's speed is exactly doubled.
The flow of time can also be reversed by holding the X button; this immediately inverts the timerate, setting everything (but the stick figure) moving backwards through time. Timerate also has a negative cap at -120spm. Time does require motion from the stick figure to flow, regardless of negativity.
Gameplay makes the stick figure out to be the only thing unaffected by the timerate, but objectively, the contrary is true: the stick figure is the only thing affected by it at all. After it clears a level (or is killed), the stick figure's movements are compiled into a video at +60spm, upon which the timerate appears to be more of a form of time travel that only the stick figure can use. When travelling in reverse through time, the stick figure's mass quite clearly inverts, as it falls "upwards" from the ground. Additionally, the stick figure always appears to be moving at +60 or -60spm—its movements, however, appear inversely faster or slower with its current timerate. For clarity, this article is written from the perspective of gameplay. The replay video was, according to a Time Signature developer, only added to break players' brains more, e.g. by seeing a stick figure "separate" into two, with one falling up, then having that stick figure "converge" with another falling down, after which the latter two promptly "disappear".
On the top screen is a score, rather like sheet music, that displays the entirety of time for that level. When at the end of a non-looping span of time, everything halts, despite the timerate not changing, and time must be reversed; the same happens when trying to reverse time past the beginning of such a span, and the timerate must then be made positive by releasing the X button. On the score are note- and glissando-like icons representing the timing of events and object motions in the level. The score is divided horizontally into "beats", colored in a rainbow-like fashion from blue to red; each "beat" represents a second of time, and objects in the level faintly glow each beat's color as it passes. The two dots of portals, mid- to late-game objects resembling repeat signs, glow the color of the beat on the other side.
Each level in the game is an area the size of the Display's screen. There are deadly obstacles such as lava, cannonballs, etc. throughout the levels.
As a rule of thumb, nothing in early levels can be modified, to avoid the possibility of temporal paradoxes; thus, some hazards can be bounced off of à la Goomba Stomp, but bouncing off of them in this fashion does not kill them nor divert their momentum. Later levels do give players tools that can be messed with, which cause "paradoxes" in the replay compilation despite counting as clearing the level. There are actually sneaky ways to beat every such level without interaction with non-inert objects, for a "good ending"-type clear, but they are difficult to discover and/or to pull off.
The goal of each level is to reach a door, which leads to the next level. Thus, the bulk of the puzzle gameplay is based on using objects in the levels at certain times, as well as managing the flow of time outright—or "timing and time management", as stated by advertising for the game.
There are several objects used throughout levels to provide some variance in gameplay and puzzle-solving.
- Ground can be stood on or bumped into from any side, and cannot be passed through by the player or by certain objects.
- Doors clear the current level and lead to the next one when touched.
- Lava is a basic hazard, usually found along the edges of the screen, though floating magma bubbles do appear in some later levels.
- Platforms are solid blocks that move tween-style between a defined set of points. Most carry the player to another part of the level, but some lead to traps.
- Trampolines bounce the player when stood on, roughly inverting their vertical momentum. In later levels, they are found embedded in walls and ceilings, but most are bound to the ground.
- Spikes are deadly.
- Cannons shoot projectiles that can help or harm the player. A cannon with a circle on it shoots cannonballs, which are bad to touch but can be stomped on. Cannons with squares will shoot solid blocks, though these can still pinch the stick figure if it is caught between a block and another solid object.
- Ghost blocks are beveled tiles appearing and disappearing at given times, with their solidity following suit. Early levels have the player timing their jumps across the blocks, but later ones have them dropping objects into ghost blocks as they appear, taking advantage of the blocks' solidity to momentarily freeze said objects in place.
- Trapdoors, hinged parts of solid terrain, rotate 90° to open and close at set times.
- Keys and locks must be connected to trigger certain events. The player can grab and discard a key simply by pressing the B button while near one. Keys lag behind the player somewhat, and the distance they are discarded depends on how far away they are from the stick figure. Sometimes keys must be thrown or dropped into a lock in a place that the stick figure would not be able to escape from itself. In addition, some unlockings must be timed relative to the level's score, for instance to give required events enough time to occur after a lock opens.
- Pendulums swing back and forth, slaughtering any stick figures they hit.
- Nopes remove from existence anything to come in contact with them. Rewinding will, however, bring said anything back into reality. They are shaped like no signs.
- Twist blocks continuously rotate; when lined up, they serve as makeshift conveyor belts.
- Bomb boxes blow up everything in a certain radius when stomped on.
- Bombs can be carried like keys. They blow up when stomped, or once they hit a wall after being thrown.
- Checker walls are sections of walls and ceilings that can be stood on when touched. The player can move the stick figure along the surface of a checker wall, and must jump off to return to normal gravity.
- Antigrav panels are sections of the background in front of which nothing can be affected by gravity. An object's momentum and velocities are preserved until it stops touching a panel. The player has lessened, more inertial control when the stick figure is in front of an antigrav panel.
- Portals lead to another portal at a point offset through time. They are ground-bound and shaped like repeat signs, with the dots lit up in the color of the time the portal leads to. A portal "closes" when it would lead to a time that doesn't exist, such as before or after a non-looping score.
- Returns, shaped like Dal Segnos, are similar to portals, leading to an exit point at another time in the score. They even have fluorescent dots and all. However, each one leads to a specific point in time, as opposed to offsetting the player. They can also be entered from any side, and are one-way.
- Time bombs completely destroy parts of the time continuum when stomped. When reached, exploded beats are "skipped over" from that point on. This affects the tweening of objects like platforms, magma bubbles, and the like, and cannon fodder can get to another location at a slightly different time. Needless to say, destroying the right piece of the score is integral to many timing puzzles, some of which are open-ended.
- Shadows are cross-sections of spheres moving along the z-axis, intersecting the two-dimensional level in the process. However, all the player sees of this is the pixelated circumference of an expanding and contracting circle. As with anything from a higher dimension, it would probably be wise for our 2D stick figure to avoid touching the shadow of a moving sphere at all costs.