Player Stats

Movement

Stamina (Short-Term Resource)

Fatigue (Long-Term Tiredness)

Fatigue accumulates across an entire play. Unlike stamina, it doesn’t recover quickly.

Example: At 0.5 fatigue, player runs at 82.5% speed. At 1.0 fatigue, 65% speed.

Carrier Moves (Ball Carrier Abilities)

These abilities are available to any ball carrier (non-QB by default; QB uses face buttons for throws). Each costs 0.2 stamina and 0.05 fatigue.

Dash (Left/Right)

Spin (360 Rotation)

Jump

Throwing & Catching

Throw Stats

Aim Assist

Catch Rates

Tackle Mechanics

Defender Fatigue (During Chasing)

Speed Burst (Defender Closing)

Scoring & Downs

Play End Conditions

1. Tackle - Defender touches ball carrier within tackle distance
2. Incomplete pass - Ball hits ground with no carrier (turnover +1)
3. Interception - Defender catches ball in flight (turnover +1)
4. Touchdown - Ball carrier reaches end zone (+7 points)

Character Roles

Offensive Roles

QB (Quarterback) - Player-Controlled

The human-controlled character. Throws the ball, moves with WASD, and triggers play start on first movement.

• Controller face buttons = throw to numbered receivers (1-4)
• Keyboard 1-4 = throw to specific receiver, Space = direct throw
• Sprint with X / Left Stick Click
• Cannot run routes or block (is_qb = true)

WR (Wide Receiver)

Primary pass catchers. Run routes downfield to get open for throws.

• Can run routes: Yes (GO, OUT, SLANT, POST, CURL, COMEBACK)
• Can block: Yes (secondary role after catch)
• Receiver numbered: 1-4 (shown as Label3D above head)
• Pre-snap: Lines up in formation, faces QB
• During play: Runs assigned route, evades defenders, chases thrown ball
• After catch by teammate: Lead-blocks for the ball carrier

TE (Tight End)

Versatile player that can catch or block.

• Can run routes: Yes
• Can block: Yes
• Behavior: Same AI as WR but typically assigned shorter routes

RB (Running Back)

Backfield player, can catch or block.

• Can run routes: Yes
• Can block: Yes
• Behavior: Typically runs shorter routes or stays in for protection

FB (Fullback)

Primary blocker role.

• Can run routes: Yes (rarely assigned routes in practice)
• Can block: Yes (primary duty)
• Behavior: Blocks for QB pre-throw, lead-blocks for carrier post-catch

OL (Offensive Lineman)

Pure blocker, protects the QB.

• Can run routes: No
• Can block: Yes
• Behavior: Finds nearest unblocked defender within 15m, chases and slows them (75% speed reduction on contact)

Defensive Roles

All defenders use LimboAI behavior trees. Their role determines which BT branch takes priority.

Blitzer

Rushes the QB directly. Assigned to first 2 defenders + possibly the 5th (50% chance).

• Speed: 1.01x max speed during rush
• Target: Always the QB while ball is in hands
• Falls back to: Chase carrier if QB throws

Man Coverage

Shadows an assigned receiver to contest catches. Assigned to indices 1-2 and 5-6 in a 10-man defense.

• Shadow distance: Stays within 2.5m of assigned receiver
• Pre-throw: Follows receiver through route
• Post-throw: Continues shadowing until catch or LOS crossed
• Falls back to: Chase carrier/ball when appropriate

Zone Coverage

Holds a field position and reads the QB. Assigned to indices 7-9 (safeties/DBs).

• Behavior: Holds zone position, faces QB
• React trigger: Ball predicted to land within 8m of zone
• Falls back to: Chase ball/carrier when triggered

Route Types

Routes define the path receivers run after the snap.

Route is complete when the receiver is within 2.0 units of the target position.

AI Behavior Detail

Receiver AI (BTSelector Priority)

1. Play ended?      -> Stop and idle
2. Moving to formation? -> Move to pre-snap position
3. Ball in air?     -> Chase ball, attempt catch
4. Running route?   -> Execute assigned route
5. Route complete?  -> Evade nearby defenders (stay open)
6. Teammate has ball? -> Lead-block for ball carrier
7. QB has ball?     -> Block nearest defender (protect QB)
8. Fallback         -> Idle

Evasion behavior (post-route):

• Defender < 4m: Full-speed evasion away from defender
• Defender 4-8m: Gentle drift to maintain separation
• No defenders nearby: Hold position facing QB
• Always biases toward end zone to stay useful

Blocking behavior:

• Finds closest unblocked defender within 15m
• Chase at full speed if > 2.5m away
• Slow pursuit (0.3x) within 2.5m
• Applies 75% speed reduction to blocked defender
• Releases block if defender escapes > 4m

Defender AI (BTSelector Priority)

1. Celebrating?     -> Idle (post-play celebration)
2. Play ended?      -> Stop and idle
3. Has the ball?    -> Stop and idle (interception)
4. Moving to position? -> Move to formation spot
5. Blitzing?        -> Rush QB at 1.01x speed
6. Man coverage?    -> Shadow assigned receiver (<2.5m)
7. Zone coverage?   -> Hold zone, read QB, react to ball
8. Ball in air?     -> Chase ball (interception attempt)
9. Ball carrier exists? -> Chase carrier (lead prediction)
10. Fallback        -> Idle

Carrier chase uses lead prediction:

• Lead time = distance / defender max speed (clamped 0-0.7s)
• Predicted position = carrier pos + carrier velocity * lead time
• Per-defender angle offset prevents stacking on same spot

Defense Assignment Distribution (10-Player Defense)

Indices 0, 3     -> BLITZ (rush QB)
Indices 1, 2     -> MAN (shadow receivers)
Index 4          -> BLITZ
Indices 5, 6     -> MAN
Indices 7, 8, 9  -> ZONE (hold field position)

For smaller defenses (3-9 players): first 1/3 BLITZ, middle 1/3 MAN, last 1/3 ZONE.

Default Offensive Lineup

From SpawnManager spawn order:

Tunable Stats (@export Variables)

These can be adjusted in the Godot Inspector: