Keep the town dry with a complete wall
To stop the tsunami, build a continuous defence around the town before you press Start Round. Dig Sand with a Spade or Shovel, pile it into a wall, then repair low sections, exposed edges, and visible Gaps before spending time on extra height. A tall wall in only one place is not enough: water can pass through a thin section or go around an unprotected side.
Your first-session target is not a perfect late-game barrier. It is a connected first line that covers the main beach approach, has no obvious opening at either end, and is packed or fixed where you have time. After the wave, use what you learned from the water path to strengthen the next weak section. The game rewards holding back waves with Coins, which you can use for better Tools, Machines, and later materials.
The game does not establish a reliable height threshold or universal wall size. Treat the wall as ready when its lowest sections and side edges are covered, rather than following a fixed number that may not fit the current beach or Wave. For the full preparation-to-impact sequence, use the beginner defense guide.
How a beach round moves from sand to tsunami
Stop the Tsunami uses a preparation-and-impact structure. During preparation, players gather material, shape the beach, and position a defence. Pressing Start Round changes the state: the Tsunami reaches the wall, and you watch for water coming over the top, around an edge, or through a Gap. Once the danger has passed, the result becomes the plan for the next round: repair what failed, improve the layout, and spend Coins on more capable equipment.
The beach can become wider after a stage is cleared while the waves get bigger. That makes the same construction habit useful across later rounds, but it does not make one wall design permanently safe. Easy, Medium, and Hard modes also mean that a layout that survives one situation may need more height, thickness, or stronger materials in another.
A good round therefore has three decisions. First, choose coverage: which beach approach and side routes must the wall close? Second, choose strength: where does the wall need height, volume, packing, or Glue? Third, choose a fallback: where can a Trench or another line slow water if the first barrier is breached? Make these decisions before starting the round, because large construction during the impact is harder to control.
Walls, tools, and water-control pieces
Use the following pieces according to the problem they solve. The table describes roles rather than fixed statistics; exact durability, costs, and unlock conditions are not established here.
| Element | What it changes | When to use it |
|---|---|---|
| Sand Wall | Creates the basic barrier from gathered Sand | Start the first line and close open beach routes |
| Tall Wall | Adds vertical protection against a larger Wave | Raise low sections after the full route is covered |
| Thick Wall | Adds material volume for a stronger impact barrier | Build on the main incoming side and vulnerable corners |
| Multi-line Wall | Leaves another barrier after the first line is damaged | Add a second or third line when the beach gives you room |
| Tamper | Packs the wall so it can last longer | Compact important sections before Start Round |
| Glue | Fixes key wall sections against early failure | Use on critical segments when the first round could remove them |
| Trench | Catches or slows water that gets beyond the wall | Dig behind or near the wall as a buffer, never as a replacement for coverage |
| Machines and advanced materials | Speed hauling or provide later construction options | Upgrade after survival, then use Gravel, Boulders, Clay, or Concrete as available |
The first three wall choices solve different problems. Height helps with water coming over the top; thickness gives the impact more material to work through; coverage prevents water from simply choosing a different route. Build in that order when time is limited: close the route, correct the lowest or thinnest section, then add strength.
Tools grow with progression. The game description starts with a toy Spade and names Shovels, a Bulldozer, a skid steer, Excavators, and a dump truck as later equipment. A machine can make a large defence practical, but it does not decide where the defence belongs. Keep checking the town-facing side, the ends of the wall, and any place where the water could bypass your work.
Materials also expand later. Wood, Ice, Black Stone, Sandstone, Gravel, Boulders, Clay, and Concrete are mentioned as progression options, but their exact strength and costs are not specified. Choose an advanced material because the current Wave demands more resilience, not because an unverified material ranking promises an automatic win.
Your first complete wall defence
- Inspect the beach before building. Look from the town toward the sea and identify the main approach, both side edges, and any low ground that could become a Gap. This is your starting checkpoint: you should be able to point to the route the first line must close.
- Gather Sand with a Spade or Shovel. Dig enough material to begin a continuous line instead of making one isolated mound. If you are playing with friends, one player can dig or drive while another starts shaping the barrier; the game describes a shared Coin wallet and shared Machines.
- Close the main route first. Pile the Sand across the incoming approach and connect the ends toward the safer sides of the town. Checkpoint: walk or look along the entire line and correct any visible opening before adding a decorative peak or a single very tall section.
- Fix the weakest visible section. Compare the wall’s low, thin, and exposed parts. Add height where a Wave could pass over, then add thickness where the wall would take the strongest impact. Do not leave the side ends low while concentrating all material at the centre.
- Pack or fix the critical segments. Use a Tamper on the sections that must survive the first impact. Use Glue on important sections when available. The supported goal is longer survival, not a guaranteed duration or a confirmed multiplier, so keep ordinary Sand available for repairs.
Fix walls and plan a multi-line defence
This moment supports the Glue and second-line advice by showing how to keep walls from failing after the first round and plan three thick walls with space between them.
- Add a buffer behind the line. Dig a Trench behind or near the wall if the layout allows it. Treat it as a second layer that can catch or slow water after a breach. Checkpoint: it should not create a new open route into town or replace a missing side wall.
Add a trench behind the tsunami wall
This moment supports the trench guidance by explaining how a trench behind the wall can catch water and provide extra protection.
- Build a second line when coverage is secure. If there is room and enough material, place another thick line behind the first and leave usable space between the lines. This gives a damaged first barrier another chance to slow the water, but it is less valuable than closing a large Gap in the first line.
- Start the round and read the breach. Press Start Round only after the key sections are complete. During the impact, watch whether water comes over the top, around an end, or through a thin or missing section. This is the completion checkpoint for the first attempt: identify the actual failure path rather than guessing from the wall’s appearance.
- Repair for the next Wave. After surviving or losing the round, return to the failure path. Patch a Gap first, raise the low section next, and then reinforce the part that absorbed the impact. If the town stays dry, still inspect the wall before repeating the process because later waves can grow larger as the beach opens.
The terminal decision is whether to spend the next Coins on construction speed or resilience. Better Tools and Machines help you gather and move material faster; stronger or later materials help the barrier handle harder impacts. Neither removes the need to inspect coverage and edges.
Priorities when the wall starts failing
- Close a Gap before making the centre taller. A hole or open side gives water a direct route into town. Stop gathering for height, patch the opening, and reconnect the wall. Once coverage is continuous, return to the lowest section.
- Repair a short wall before adding a third line. A thin or low part can let the Wave pass while unused space sits behind it. Add Sand to the weak segment, then consider another line only after the first line is credible from end to end.
- Use the breach direction as your next-round plan. If water came over the top, raise and thicken that segment. If it came around the side, extend the wall or close the edge. If it passed through a thin section, add volume and pack it with the Tamper when possible.
- Do not rely on a Trench to replace a wall. If water enters through an open side, dig no further until the route is closed. Keep the Trench as a buffer behind a real barrier, and inspect whether your digging has created another path toward town.
- Do not attempt major construction too late. When the Wave is already moving, switch from expansion to the fastest supported repair: patch the nearest Gap, reinforce the town-facing failure point, and use Glue or the Tamper on a section that can still affect the impact. Save ambitious multi-line work for the next preparation phase.
- Coordinate jobs in multiplayer. Because Coins and Machines are shared, avoid having everyone dig the same patch. Assign gathering or driving to one player, wall shaping to another, and inspection or repair to a third. If the wall fails, regroup around the actual breach instead of rebuilding separate unconnected mounds.
Survival is a progression decision, not just a building contest. Clear the current stage, collect the resulting Coins, and improve the tool or material that addresses your last failure. As the beach widens and Waves become bigger, keep the same priority order: complete coverage, fix the weakest section, pack or fix key segments, then add a second line or stronger material.
First-time Stop the Tsunami wall questions
Should I build one very tall wall or several connected walls?
Build a connected first line before making any one section exceptionally tall. A single high point does not protect the town from a Gap, low edge, or water that goes around the side; add another line only after the main route is covered.
What does a Trench do behind a tsunami wall?
A Trench can catch, slow, or redirect water that gets beyond the wall, so it works as a buffer. It does not replace a complete wall, and digging it should not open a new route toward the town.
What should I upgrade after a wall fails?
Use the breach to choose the upgrade. Better Tools or Machines help when gathering and hauling are too slow, while thicker construction, a Tamper, Glue, or later materials address a barrier that breaks or is too weak for the next Wave.