"Two protagonists escape an inverted space-time inside an hourglass together."
Lead Game Designer | 9-Person Course Project | Dec. 2020
When Tenet Meets Badeline in Celeste
"Time Clamp Adventure"
Time clamp movement is the core definition in Christopher Nolan's film Tenet. In the movie, the red protagonist moves "forward" in time and the blue one moves "backward". In the game, we create a time inversion mechanic so the player can experience both protagonists in one linear level.
Badeline
Badeline is the main antagonist from Celeste. She haunts Madeline, the protagonist of the game, in Chapter 2 by simply following Madeline's track a few seconds later. Once Madeline runs into Badeline, she will die. This part of gameplay is like a self-confrontation, bringing so much excitement and thrills to the game. What's more, it also adds route strategy into a game that centers on platform challenges, bringing more fulfillment to players.
Experience Goal
The fulfillment after solving a difficult space-time puzzle with a well-thought-out plan.
Wanting to punch yourself after being trapped or killed by yourself.
Tension and thrills during the confrontation between the two protagonists.
Design Goal
Maintain the time-inversion concept in a concise and simple mechanic.
Let the inversion affect all level elements.
A smooth experience flow consisting of the cycle of learning, practicing and challenging.
Core Gameplay
Level Phase I
Controllable character: RED
RED collects all the gems and reaches the terminal within the time limit to enter Phase II and trigger the space-time inversion.
Space-Time Inversion
Rotate the scene by 180 degrees
Start the time inversion
Regenerate the gems only for BLUE to collect
Level Phase II
Controllable character: BLUE
Non-controllable character: RED
Except BLUE, all elements including RED will rewind. If BLUE runs into RED, they will both die. BLUE must collect all the gems and reach the new terminal within the time limit.
Level Design
The game consists of dozens of levels. We need to arrange the levels and keep track of all the mechanics. To design the experience as a whole, we use two difficulty curves. Puzzle difficulty refers to "How hard is it for a player to figure out the solution?" Skill difficulty refers to "How hard is it for a player to execute the solution with the control scheme?"
The overall difficulty steadily rises as players become more and more experienced in their skills and understand the mechanics better. Periodic hard puzzles serve as challenges for players, requiring understanding of the mechanics and a well-thought-out plan as well as good execution. Additionally, easy mechanics intros serve as breaks after challenges.
Level Examples
LEVEL 1 - Intro
This level is designed to let players learn the basic controls as well as the core mechanics. The level used to be completely centrosymmetric, but later we found players didn't notice the space upside down and the time inversion due to the structure. After we redesigned the level, RED and BLUE now have a completely different experience so that players will notice the difference between the two phases.
LEVEL 2 - Practice
This level introduces the mechanics of the trigger and the spike. It is still easy to pass. Compared to Level 1, it provides more excitement since BLUE and RED have much more interaction and confrontation in the center of the level structure.
LEVEL 3 - Challenge
This level combines the trigger and the time mechanics to create a puzzle. Most importantly, it introduces a mindset that RED can help with BLUE, which goes through all the puzzles later. The level requires players' understanding of the time inversion and its effect on the trigger.
To solve the puzzle, RED needs to wait for several seconds just before reaching the terminal. Then BLUE uses the extra time to pass the spike area.
In-game texts between levels: Beginning
Ending level allows players to control two characters at the same time
Story
The game opens with a monologue from the protagonist, who accidentally enters the world of the hourglass. The protagonist determines to use the power of the gems and embarks on a journey to collect all the gems inside the hourglass.
Later in the story, though the protagonist incessantly seeks the gems, the amount is not enough to provide power for the escape.
After finding the last gem, the protagonist becomes desperate, and the world is also losing its balance without the gems. The chaos in the flow of time results in two protagonists' simultaneous moves. After they run into each other, the power from the annihilation and the power from the collected gems merge together and release in an instant. Eventually, the protagonist escapes from the hourglass before it collapses.
Prototype & Playtest
Here's an example of how we iterate the game. At an early stage, we wanted to crystalize the core gameplay and make sure that the simplest gameplay satisfies our experience goal. We implemented 3Cs, the Space-Time Inversion mechanic in the first version of the prototype. Thanks to the open courses, we were able to invite 15 game designer from Tencent to playtest our prototype.
Prototype V1
Problems: We find that the conflict between Red and Blue hardly appeared in Phase II. As a result, the game experience is bored and plain.
Solution: Add compulsory collectibles in V2.
Result: Red and Blue both are required to come to the same place for collecting gems. Each gem is like a conflict center, where Blue is likely to run into Red.
Prototype V2
Problems: The movement between Red and Blue is asynchronous. In some cases of the playtest, some players find a general cheat method: avoid any interaction between Red and Blue by simply giving way to Red.
Solution: Add a countdown in V3.
Result: With the pressure from the countdown, Red and Blue both are forced to move. The player needs to have a plan of Red's and Blue's routes, and improvise during the execution: running, dodging, detouring, etc.
Prototype V3
Eventually, the prototype V3 provides the tension as well as the process of solving time puzzles that we expected. Thus, we finalize the core gameplay in V3, which is later polished in the production.
Prototype V1
Prototype V2 (Added Collectibles)
Prototype V3 (Added Countdown)