The Playable Multiplane: Uses of the Z-Axis In Leila and Paper Mario: The Thousand-Year Door

May 26

8 min read

Abstract

The multiplane camera produced depth on flat screens by separating artwork into layers and moving them at different speeds. In film animation, this depth belonged to the camera, which operated through a dedicated mechanical apparatus. In games, the same layered logic both enriches the player's experience and becomes a controllable mechanic. Here, the Z-axis interaction functions not only as an atmospheric, immersion-enhancing experience inherited from the classic multiplane camera but also as an active part of the game's mechanical system. This essay examines how Paper Mario: The Thousand-Year Door and Leila each bring a new perspective to the player's experience by engaging with the Z-axis introduced to the medium by the multiplane camera, in two distinct ways. Paper Mario uses depth to foreground staging and construction, while Leila uses depth to support human memory, personal journey, and emotional transformation. These two approaches appear worth examining not only as technical methods, but also in terms of what they represent mechanically and symbolically within the game world.

1. From Camera Depth to Playable Depth

In the late 1930s, Disney introduced a new solution to a persistent visual problem: how to simulate space and depth in cel animation without full volumetric environments. The multiplane camera¹ was a layering system that separated foreground, midground, and background artwork across stacked planes to create depth and parallax under camera motion (Walt Disney Family Museum, 2018).

Figure 1: Frames from Walt Disney's The Old Mill²

Digital games inherit the same layered logic. At the time, the full range of contributions this kind of system might offer to games had not yet been explored. Initially, games applied it much as animation had, to produce the appearance of depth and to establish a positional relationship between the player and the world through a convincing optical illusion. Moon Patrol³ stands as one of the earliest examples of this inheritance (Irem, 1982).

Figure 3: Moon Patrol (1982)

In the decades that followed, this technique, by then nearly half a century old, began to be reshaped by the specific character of the game medium. Once movement is tied to player input, depth becomes part of the game's mechanics and the player's interactive experience, rather than only a visual effect. This shift aligns with Bolter and Grusin's distinction between transparent immediacy and hypermediacy: interfaces can either hide mediation to support presence or expose mediation as part of the experience (Bolter & Grusin, 1999).

Figure 4: Paper Mario: TTYD (2004) Thin Passage

Early examples of in-game spaces built from layered 2D art tend toward immediacy in their use of Z-axis behavior. The games examined in this essay engage with this inheritance differently: both adopt a hypermediacy-oriented approach, interpreting depth along the Z-axis as a rhetorical position, either revealing the apparatus or recruiting it for absorption. In practical terms, Paper Mario keeps mediation overt (see Figure 4), while Leila tries to let mediation recede under mood and memory (see Figure 5).

Figure 5: Leila (2025) Forest Environment

Methodologically, this essay uses close reading of the two games, supported by official paratexts and limited external commentary, with intentionally asymmetrical evidence between the case studies.

2. Stage Depth and Hypermediacy in Paper Mario

Paper Mario: The Thousand-Year Door is commonly framed as "2D in 3D," but the stronger point is that it insists on material flatness while still organizing scenes in depth⁴. Campana's analysis of Paper Mario's 2.5-dimensionality provides a structural foundation for this reading: paper-like materiality is not cosmetic but actively organizes how interaction and perception operate (Campana, 2015). In TTYD, characters read as paper cut-outs, and environmental layers are visibly staged. The game does not try to hide this; if anything, it seems to enjoy reminding you of it.

Combat is the clearest example. In the close reading of battle scenes in the 2024 remake⁵, encounters are framed as stage events: curtains open to reveal the arena, lighting isolates action, and falling set pieces can interrupt turns (Intelligent Systems, 2024)⁶. Nintendo's overview similarly foregrounds audience participation by describing a battle crowd that can either assist the player or interfere (Nintendo, 2024). Taken together, these details frame depth as a matter of position on a stage, where you stand relative to the action, the crowd, and the set, rather than as a convincing illusion of space (see Figure 6).

Figure 6: Paper Mario (2024) Combat Scene

This makes the Z-axis agency in Paper Mario largely demonstrative. When Mario moves deeper into the screen, it does not feel like entering somewhere; it feels like walking further into someone's set design. The player operates in a world that constantly reminds them it is materially fabricated. In Bolter and Grusin's terms, this is a hypermediated strategy: the medium remains visible and pleasurable as medium (Bolter & Grusin, 1999).

This logic extends beyond combat. In traversal and puzzle moments, paper transformations turn movement into material demonstration: the avatar folds, bends, or reconfigures to pass through space. Flatness is not something the game apologizes for or disguises; it is the actual system you play with.

In short, Paper Mario uses multiplane inheritance to embrace artifice. Depth, here, keeps pointing back at the craft. It is not asking you to forget that someone built this.

3. Inward Depth and Affective Immediacy in Leila

Leila is also built from layers, but the intention feels completely different from the start. Official paratexts frame the game as traversing phases of one person's life and reconstructing memory through interactive scenes (Ubik Studios, n.d.; Steam, 2025)⁷. The spatial structure is similar, but where Paper Mario wants you to notice it, Leila would rather you didn't.

Two published reviews describe brief puzzle-driven progression through emotionally coded environments, with particular emphasis on painterly backgrounds, subdued motion, and atmosphere (Adventure Game Hotspot, 2025; Gamecell, 2025). Moving forward through these scenes feels less like navigating a level and more like walking into someone's memory, which, in the game's logic, is exactly what it is.

Figure 7: Leila - Hidden Object Puzzle

A recurring transition sequence provides a concrete example⁸. The player advances through a first-person woodland corridor between episodes, follows signs toward the next memory, and can click silver-veined trees to reveal still-image fragments from other moments in Leila's life (Adventure Game Hotspot, 2025). Combined with the game's minimalist "move forward and interact" loop (Gamecell, 2025), this turns layered depth into a navigable memory interface rather than a passive background.

Figure 8: Leila - The atmosphere of the forest changes from spring to fall

What matters here is the relation between motion and atmosphere. There is no real mechanical pressure. What you control, more than anything, is how quickly you move through feeling. This is a long way from Paper Mario's relationship with depth. The goal is not to reveal structure; it is to pull you into a mood slowly enough that you stay in it.

Figure 9: Leila - Body Positioning Puzzle

Material treatment is crucial here. Painted textures and softened transitions reduce hard segmentation between planes, encouraging visual continuity. Paper Mario's hard edges keep reminding you that layers exist. Leila blurs them, quietly, so you stop noticing where one plane ends, and another begins. The interface is still mediated, but it is designed to retreat perceptually so emotional narration can dominate.

Both games use layered depth, but what Leila does with it is closer to atmosphere management than spatial design. Depth is not there to expose the set; depth is there to pull the player through a personal archive⁹.

4. Comparative Synthesis

Both games can be read as descendants of the same historical technique family: stacked planes, parallax cues, and controlled relations between flatness and depth. But what they ask depth to mean could not be more different.

In Paper Mario, depth is constantly announcing itself; this world is built, staged, put together on purpose. The pleasure, if you want to put it that way, comes from playing inside something that never pretends to be real. Leila does it differently. Depth there is meant to feel personal, almost private, an invitation inward, toward memory, rather than outward toward the spectacle of craft.

This contrast can be framed as a material contract, an analytic term rather than a claim about literal rendering technology. Paper Mario's implicit agreement with the player is: I will always show you how this works. Leila's is closer to: I will keep the machinery out of your way so you can feel what matters.

Therefore, while Leila uses the depth as a passage of memories, Paper Mario makes space to act in.

5. Projection on Contemporary Game Experience

This shift from camera-owned to player-operated depth is part of why multiplane-derived design keeps showing up in contemporary games. Contemporary players expect atmospheric richness and immediate response at once. These demands can conflict: more visual flourish can reduce clarity of control if timing is not carefully tuned. Design literature on game feel treats responsiveness as central to perceived quality (Swink, 2008), which means visual depth, however atmospherically rich, cannot come at the cost of readable control.

This logic appears across contemporary 2.5D design, where layered depth still carries atmosphere but is tuned around controlling readability (e.g., Inside, Ori and the Will of the Wisps, Little Nightmares) (Moon Studios, 2020; Playdead, 2016; Tarsier Studios, 2017). What survives from analog animation into contemporary 2.5D design is not just a look. It carries questions about player experience, such as the depth amount to keep the player in control, and to let the player engage with the game world.

6. Conclusion

The multiplane camera solved a film-era problem of representing depth with layered 2D images. In games, that same logic gets handed to the player, but what players do with depth turns out to depend entirely on what the game has decided depth is for. Paper Mario and Leila sit at different ends of that question. Paper Mario uses depth to put construction on display; Leila uses it to quietly disappear into feeling. The technical ancestry is the same. What they are trying to do with it is not the same. For anyone designing with layered depth, the practical question is not whether it looks atmospheric enough. It is whether the depth is telling the player what the game actually needs them to feel, and whether the game's material choices are backing that up.

References

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https://adventuregamehotspot.com/review/4639/leila
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