Shipwright's Manual: Physics, Joinery & Block Craft

THE TIMBERHARBOUR HIGH-ALTITUDE DRAFTING LOFT & ENGINEERING REFERENCE

Inspect the structural systems, multiplayer rules, and verified facts of every sandbox on our slipways.

High under the red-cedar roof trusses of the TimberHarbour Drafting Loft, twelve-foot Master Shipwright Timbor Keel and osprey test-pilot Harbra Vane set scale models of modular biplanes, brass marble trestles, and voxel keeps across the long drafting tables. While our coastal drydock and its guardians are shipwright fiction, every specification recorded in this manual is drawn from each publisher's official information (checked on October 26, 2026). All nine featured titles are free-to-play browser games whose in-game purchases, optional subscriptions, ads, account options, and player chat rules are detailed per game below.

Inspect Master Comparison Table I. Airframes & Logic II. Gravity & Demolition III. Voxel Realms

Timbor Keel and Harbra Vane inside the sunlit TimberHarbour Drafting Loft inspecting miniature wooden block-planes, marble tracks, and voxel castle models. — **Loft Inspection Table:** Timbor Keel's quick-release forearm workbenches and Harbra Vane's spruce-ribbed wing gauges calibrate balance before a single beam reaches the slipway.

**Loft Inspection Table:** Timbor Keel's quick-release forearm workbenches and Harbra Vane's spruce-ribbed wing gauges calibrate balance before a single beam reaches the slipway.

Master Drydock Comparison Ledger

NINE BROWSER SANDBOXES COMPARED BY CONSTRUCTION SYSTEM, PLAY MODE & VERIFIED FACTS

Before you step out onto the launch piers, use this cross-harbour ledger to compare how each game handles construction physics, solo workbenches versus shared online worlds, browser compatibility, and monetization or chat settings.

Sandbox & Developer	Slipway Bay & Construction System	Play Mode & Sharing	Browser Support	Price, Purchases & Subscription	Ads, Account & Player Chat
Build A Plane Ninjaking (2026)	Slipway I: Airframes Modular block vehicles; simulated lift, drag, thrust, weight, balance, and friction.	Single-player campaign objective levels (with time limits) & free Sandbox Mode.	Desktop browser only (Unity 6)	Free to play with no in-game purchases; no subscription.	Ads: Yes · Account: None · Chat: No
Mechacraft.io Mechacraft.io (2026)	Slipway I: Airframes & Logic Modular blocks, wheels, engines, and connected logic gates in a physics sandbox.	Multiplayer public worlds (5,000 build points), custom lobbies, & attributed blueprint remixing.	Desktop & mobile browsers	Free to play with no in-game purchases; no subscription.	Ads: Yes · Account: Optional · Chat: Yes
Build League OnRush Studio (2025)	Slipway I: Airframes & Courses 3D airplanes, cars, and trains upgraded with better engines, fuel, and parts via in-game cash.	Single-player or online multiplayer obstacle courses across varied maps.	Desktop, phone & tablet browsers	Free to play with no in-game purchases; no subscription.	Ads: Yes · Account: None · Chat: No
Marble Run Simulator Tiaratum Games (Sven Taton) (2024)	Slipway II: Gravity Tracks 3D ramps, turns, and elevators with free camera rotation; includes Gravitology puzzle game.	Single-player builder, pre-built demo machines, URL track sharing, & moderated Showcase list.	Desktop & mobile browsers (BabylonJS)	Free to play with no in-game purchases; no subscription.	Ads: Yes · Account: None · Chat: No
Line Rider Boštjan Čadež (2006)	Slipway II: Gravity Tracks 2D freehand line-drawing track canvas with simulated sledder playback physics.	Single-player track drawing & playback sandbox.	Browser canvas (mobile browser support unverified)	Free to play with no in-game purchases; no subscription.	Ads: No · Account: None · Chat: No
Build and Crush Ctrl4ltDel (2019)	Slipway II: Demolition Piers Block structures (stone, wood, glass, TNT, animals) tested against 20+ weapons and disasters.	Single-player build & crush; publish builds, remix allowed creations, and vote on others' work.	Desktop browser only	Free to play with no in-game purchases; no subscription.	Ads: Yes · Account: Optional · Chat: No
Bloxd.io Bloxd LTD	Slipway III: Voxel Realms Voxel block placement, terrain shaping, resource gathering, and parkour/combat mechanics.	Multiplayer modes: survival, peaceful building, bedwars, skywars, parkour, & player-made games.	Desktop & mobile browsers	Free to play; in-game purchases: Yes (Shop for registered players) & optional "Get Super" subscription.	Ads: Yes · Account: Optional · Chat: Yes
CubeRealm.io Voxiom.io (2024)	Slipway III: Voxel Realms Voxel resource mining, tool crafting, chunk protectors with build allowlists, from skylands to caverns.	Multiplayer servers: Peaceful (health regen, optional PvP), open-world PvP Survival, & Creative.	Desktop & mobile browsers	Free to play with no in-game purchases; no subscription.	Ads: Yes · Account: Optional · Chat: Yes
Vectaria.io Vectaria	Slipway III: Voxel Realms Voxel digging, crafting, and settlement building with four starting characters.	Multiplayer realms: survival with PvP toggle, full PvP survival, & open Creative mode.	Desktop & mobile browsers	Free to play; in-game purchases: Yes (skin store, VIP/gift pass, "GET STARTER" offer) & optional subscription.	Ads: Yes · Account: Optional · Chat: Yes

Slipway I Specifications: Airframes, Engines & Logic Gates

AERODYNAMIC BALANCE, MODULAR PROPULSION & CIRCUITRY

Harbra Vane locks her copper-flapped primary feathers into cockpit frames to test how each vehicle sandbox treats centre of mass and propulsion. In these three games, your chassis is only as reliable as the thrust, wheel torque, and logic wiring you bolt onto it. All three titles in Slipway I are free to play with no in-game purchases.

Flight & Chassis Physics: Build A Plane models six distinct forces (lift, drag, thrust, weight, balance, friction) in Unity 6 on desktop.

Logic & Blueprints: Mechacraft.io pairs wheels and engines with logic gates, 5,000-point public lobbies, and attributed blueprint remixing.

Course Progression: Build League rewards obstacle-course runs with in-game cash to buy upgraded engines, fuel, and airframe parts.

A modular aircraft built from spruce blocks, copper fuel tanks, propellers, and booster rockets launching off a coastal timber slipway into golden clouds.

Build A Plane

Ninjaking · Creative Vehicle Sandbox (2026)

Snap modular blocks together to engineer custom planes, cars, rockets, and experimental contraptions in your desktop browser. Every launch tests your frame against simulated lift, drag, thrust, weight, balance, and friction across timed objective levels or open Sandbox Mode.

Platform & Engine: Desktop browser only (Unity 6; active development with new blocks and levels planned).
Play Modes: Solo campaign levels with objectives and time limits, plus unrestricted Sandbox Mode.

Price: Free to play · In-game purchases: None

Ads in game: Yes
Account needed: No
Chat with other players: No
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Ninjaking's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

Two custom contraption vehicles built from interlocking timber blocks, wheels, engines, and glowing cyan logic gates testing their suspension on a shipyard ramp.

Mechacraft.io

Mechacraft.io · Multiplayer Machine Sandbox (2026)

Assemble blocks, wheels, engines, and logic gates into working cars and complex machines, then drive and refine them in a shared physics sandbox. You can build in custom multiplayer lobbies, remix other players' published blueprints, and test every circuit.

Lobby & Blueprint Rules: Public worlds grant 5,000 build points per player; custom public lobbies let you set map, player count, and build points.
Access & Languages: Playable without an account (optional Discord or CrazyGames sign-in) across 15 languages on desktop and mobile browsers.

Price: Free to play · In-game purchases: None

Ads in game: Yes
Account needed: Optional
Chat with other players: Yes
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Mechacraft.io's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

A custom block airplane, off-road buggy, and rail car racing through a timber obstacle course of loops and spinning wheels above a coastal fjord.

Build League

OnRush Studio · 3D Vehicle Obstacle Sandbox (2025)

Construct airplanes, cars, and trains in 3D, then pilot your rigs through obstacle courses across varied maps in solo or online multiplayer runs. Distance and clean driving earn in-game cash to unlock stronger engines, extra fuel, and fresh parts.

Studio & Devices: Built by Amsterdam-based OnRush Studio B.V.; runs in desktop, phone, and tablet browsers.
Upgrade Loop: Earn in-game cash from obstacle runs to purchase parts, upgraded engines, and fuel capacity.

Price: Free to play · In-game purchases: None

Ads in game: Yes
Account needed: No
Chat with other players: No
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on OnRush Studio's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

Slipway II Specifications: Gravity Flumes, Tracks & Demolition

KINETIC MARBLE TRESTLES, VECTOR SLED LINES & STRUCTURAL COLLAPSE

Down by the breakwater anvils, Timbor Keel braces his mortise-and-tenon shoulders against falling weights and blast waves. Two of these sandboxes let you guide rolling spheres or a sledder along precision-engineered slopes, while the third invites you to raise block masonry and test it against more than twenty destructive forces. Each game in Slipway II is free to play with no in-game purchases.

3D Track & Puzzle Suite: Marble Run Simulator pairs free-camera 3D track assembly and URL sharing with the Gravitology gravity puzzle mode.

Pure Vector Sledding: Boštjan Čadež's Line Rider (2006) runs with no ads, no accounts, no chat, and no in-game purchases.

20+ Demolition Hazards: Build and Crush lets desktop builders publish, remix, and level block builds using cannons, tornadoes, meteorites, or a black hole.

An intricate three-dimensional timber and brass marble run with spiral ramps, funnels, and a vertical elevator carrying glass and metal marbles.

Marble Run Simulator

Tiaratum Games (Sven Taton) · 3D Kinetic Track Builder (2024)

Piece together intricate 3D marble machines from ramps, banked turns, and vertical elevators, then release the spheres and orbit the camera to watch gravity work. Study pre-built demo runs, solve Gravitology puzzles, or share your own track URLs.

Engine & Sharing: Powered by BabylonJS in English and French; share creations by URL or browse the moderated Showcase list.
Bonus Mode: Title screen includes Gravitology, a dedicated gravity puzzle game alongside the sandbox builder.

Price: Free to play · In-game purchases: None

Ads in game: Yes
Account needed: No
Chat with other players: No
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Tiaratum Games (Sven Taton)'s official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

A sweeping ribbon-like timber track curving into a giant loop over a coastal canyon as a wooden sled rides along the crest.

Line Rider

Boštjan Čadež · Physics Track Drawing Sandbox (2006)

Sketch freehand lines across a blank canvas to engineer hills, loops, and precisely angled catch-ramps, then press play to watch a sledder ride your course under simulated physics. Every curve and gap rewards patient tuning and clean geometry.

Heritage & Simplicity: Created by Boštjan Čadež and first released September 23, 2006.
Zero Distractions: Free to play with no in-game purchases, no ads in game, no account requirement, and no player chat.

Price: Free to play · In-game purchases: None

Ads in game: No
Account needed: No
Chat with other players: No
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Boštjan Čadež's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

A block-built tower of wood, stone, glass, and red TNT crates on a harbour pier breaking apart mid-air under a cannon shot and coastal whirlwind.

Build and Crush

Ctrl4ltDel · Block Construction & Destruction Sandbox (2019)

Raise detailed structures from stone, wood, glass, and TNT on desktop, then unleash over twenty weapons and disasters—from cannons and tornadoes to meteorites—to test their collapse. You can also publish builds, remix creations, and crush other players' work.

Community Workshop: Rebuilt for the web in v2.0.0 with remixing (when allowed by the creator) added in v2.4.0 across 24 languages.
Platform: Desktop browser only; optional account saves builds, votes, and follower notifications without player chat.

Price: Free to play · In-game purchases: None

Ads in game: Yes
Account needed: Optional
Chat with other players: No
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Ctrl4ltDel's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

Slipway III Specifications: Voxel Wharves & Shared Block Realms

MULTIPLAYER SURVIVAL, CREATIVE CHUNK CLAIMS & ACCOUNT DETAILS

Beyond the outer log-booms lie shared voxel realms where you build alongside—or compete against—other players in real time on desktop and mobile browsers. Because all three titles include multiplayer lobbies and in-game player chat, pay close attention to each game's verified facts block regarding optional accounts, store purchases, and subscriptions.

Purchases & Subscriptions: CubeRealm.io is free to play with no in-game purchases; Bloxd.io and Vectaria.io are free to play and include in-game store purchases plus optional subscriptions.

Land Protection & Modes: CubeRealm.io offers chunk protectors with build allowlists, /sethome, and /tpa alongside Peaceful, PvP Survival, and Creative servers.

Guest Play vs. Accounts: All three allow guest play with optional registration to save progress or access account-linked features.

A vibrant voxel harbour realm with floating sky-islands, timber bridges, parkour stepping blocks, and fortified block towers over turquoise water.

Bloxd.io

Bloxd LTD · Multiplayer Block-World Modes

Jump straight into a browser collection of multiplayer block worlds spanning survival, peaceful building, parkour courses, bedwars, skywars, and custom player-made games. Gather resources, shape terrain, and team up or compete with other players across dozens of modes.

Modes & Access: Instant guest play with auto-generated names or optional login to save progress across 20 languages.
Store & Subscription: Includes an in-game Shop (store purchases for registered players) and an optional "Get Super" subscription.

Price: Free to play, optional subscription · In-game purchases: Yes

Ads in game: Yes
Account needed: Optional
Chat with other players: Yes
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Bloxd LTD's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

A vertical voxel landscape showing a sunlit floating sky-island of cedar trees and timber bridges above a glowing crystal cavern with mine trestles.

CubeRealm.io

Voxiom.io · Multiplayer Voxel Survival & Creative (2024)

Mine timber and ore, craft tools, and trek from floating sky islands down to deep caverns in an online block world. Choose Peaceful survival, open-world PvP Survival with chunk protectors, or Creative mode for unrestricted building with other players.

Server Tools: Supports Peaceful, PvP Survival, and Creative servers; Survival includes /sethome, /tpa teleport requests, and chunk protectors with a build allowlist.
Monetization & Chat: Free to play with no in-game purchases, ad-supported via AdinPlay, with enforced Chat Rules.

Price: Free to play · In-game purchases: None

Ads in game: Yes
Account needed: Optional
Chat with other players: Yes
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Voxiom.io's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

A voxel coastal settlement combining an ornate timber guildhall and dockside crane on the water with a fortified log palisade and watchtowers on the landward side.

Vectaria.io

Vectaria · Multiplayer Block Building & Survival

Pick one of four starting characters and step into a multiplayer block realm built for digging, crafting, and settlement raising. Switch between peaceful survival with a PvP toggle, full PvP survival against other players, or open Creative building.

Modes & Languages: Four starting characters; PvP survival, survival with PvP toggle, and Creative mode across 45 languages on desktop and mobile.
Store & Passes: Client includes a skin store, VIP pass/gift pass modules, and a "GET STARTER" offer.

Price: Free to play, optional subscription · In-game purchases: Yes

Ads in game: Yes
Account needed: Optional
Chat with other players: Yes
Facts checked: October 26, 2026

Source & rating

ESRB rating for the browser version: none found (checked October 26, 2026) · Based on Vectaria's official information, checked October 26, 2026.

Opens the game's official site. Its own terms and privacy policy apply.

Visit Official Site

How TimberHarbour Verifies Drydock Specifications

Our game guides are based on information published by each game's developer or publisher and on official store pages, checked on October 26, 2026. We don't score or rate games.

Return to the Great Slipway About & Verification Charter