Combat Guide
Sans Attack Patterns Explained
Sans attacks look chaotic at full speed, but most sequences are combinations of a few recurring pattern families. Learn the visual cue, choose the smallest safe movement, and practice the same response until it becomes predictable.
How to read a pattern
Look for the first stable clue: an opening between bones, the direction of gravity, a platform height, or the lane marked by a blaster. Decide where the safe space will be before moving. Following the hazard with your eyes often causes late reactions; tracking the next open area gives you a destination.
Most failed attempts come from correcting twice. A large movement overshoots the gap, then a second correction runs into the next hazard. Start with short taps and increase the distance only when the pattern requires it.
Four pattern families to recognize
Bone gaps and walls
Rows or columns of bones leave a deliberate opening. Read the gap first, then use one controlled movement to enter it.
Blue-soul platforms
Gravity limits free movement and turns the upward input into a jump. The safest jump is usually the lowest one that clears the obstacle.
Gravity throws
The soul is pushed toward an edge of the battle box. Prepare for the landing direction and move only after you can see the next hazard.
Gaster Blaster lanes
Skull-shaped blasters telegraph a firing lane before the beam appears. Leave that lane without drifting into a second telegraph.
Bone patterns: move toward the gap
Bone walls reward early positioning more than fast movement. Identify whether the opening is high, low, left, or right, then enter it with one clean input. When several walls arrive in sequence, return only as far as needed for the next opening instead of automatically returning to the center.
Platform patterns: control jump height
Blue-soul platform attacks behave more like a compact platformer. Watch the floor and the next platform rather than the soul itself. Use short jumps for low bones and reserve longer holds for obstacles that clearly require more height. Landing near the middle of a platform leaves room for the next adjustment.
The simulator is not a frame-perfect copy of Undertale. Its original project notes acknowledge differences in the heart hitbox and in the acceleration of specific platform attacks, so practice results should be treated as simulator-specific.
Gaster Blasters: leave the marked lane
A blaster gives a brief directional warning before its beam fills a lane. Move perpendicular to that lane and stop once you are clear. During overlapping sequences, check where the next blaster is aiming before committing to a long escape path.
A repeatable practice routine
- Name the pattern family before trying to optimize the dodge.
- Choose one visual cue, such as the gap or firing lane, and watch only that cue.
- Repeat the pattern with smaller inputs until the route is stable.
- Practice the transition into the next pattern, not only the isolated attack.
Source note
Bad Time Simulator is a Construct 2 clone of the Sans fight. The developer documents known differences from the original game in the Jcw87 project repository.