Endless mode
After wave 20 Brotato 1.1.15.4 keeps going: waves 11–20 repeat at 60 seconds each with int(wave ÷ 10 × 2) extra enemy groups, enemy HP grows by 1 + endless factor × 2.25 and damage by 1 + endless factor, where the endless factor is ((wave − 20) × (wave − 19) ÷ 2) ÷ 100 × (2 + 0.2 per wave past 35). By wave 30 enemies have ×3.5 HP; by wave 40, ×15.2. In the site's simulation the furthest-going build is Jack with Laser Gun (wave 28.2 on average).
How enemies and the shop scale
| Wave | Endless factor | Enemy HP × | Enemy damage × | Extra groups | 50-material item costs | First reroll | Baby Alien HP |
|---|---|---|---|---|---|---|---|
| 21 | 0.02 | ×1.0 | ×1.0 | 4 | 176 | 23 | 45 |
| 22 | 0.06 | ×1.1 | ×1.1 | 4 | 184 | 25 | 51 |
| 25 | 0.30 | ×1.7 | ×1.3 | 5 | 212 | 29 | 85 |
| 30 | 1.10 | ×3.5 | ×2.1 | 6 | 280 | 39 | 212 |
| 35 | 2.40 | ×6.4 | ×3.4 | 7 | 384 | 51 | 454 |
| 40 | 6.30 | ×15.2 | ×7.3 | 8 | 655 | 73 | 1229 |
| 50 | 23.25 | ×53.3 | ×24.3 | 10 | 1977 | 135 | 5385 |
| 60 | 57.40 | ×130.1 | ×58.4 | 12 | 5116 | 228 | 15748 |
| 80 | 201.30 | ×453.9 | ×202.3 | 16 | 21867 | 515 | 73082 |
| 100 | 486.00 | ×1094.5 | ×487.0 | 20 | 63830 | 957 | 219995 |
How this is worked out
RunData.get_endless_factor, EntityService.get_final_enemy_health/damage (Danger 0, one player, no curse), ItemService.get_value and get_reroll_price, ZoneService.get_wave_data. Harvesting shrinks 20% a wave after wave 20 instead of growing 5%.
Extra endless enemies
The game adds groups of these after wave 20 (Crash Zone; Nightmare uses its own list).
Tentacle
Lamprey
Slasher Egg
Fly
Horned Bruiser
Horned Charger
Pursuer
Buffer
Spawner
Builds that go furthest
Simulated: each character's best three Danger 5 builds, 200 endless runs each, stopped at wave 100. Endless tier list
| Character | Start with | Average wave | Top 10% | Best |
|---|---|---|---|---|
 Jack | Laser Gun | 28.2 | 36 | 38 |
 Multitasker | SMG | 26.8 | 35 | 36 |
 One-Armed | Double Barrel Shotgun | 26.1 | 29 | 35 |
 Renegade | Ghost Scepter | 25.7 | 29 | 38 |
 Masochist | Ghost Axe | 25.5 | 29 | 36 |
 Cyborg | Double Barrel Shotgun | 25.3 | 35 | 38 |
 Brawler | Fist | 25.3 | 27 | 29 |
 Arms Dealer | Pistol | 25.1 | 28 | 37 |
 Sick | SMG | 24.4 | 28 | 37 |
 Soldier | Double Barrel Shotgun | 24.4 | 28 | 37 |
 Knight | Fist | 24.3 | 26 | 29 |
 Mutant | Revolver | 23.5 | 35 | 37 |
 Generalist | SMG | 23.3 | 27 | 36 |
 King | Fist | 22.8 | 26 | 29 |
 Old | Double Barrel Shotgun | 22.7 | 29 | 38 |
 Ranger | Double Barrel Shotgun | 22.3 | 29 | 36 |
 Entrepreneur | Fist | 22.1 | 26 | 29 |
 Well-Rounded | Fist | 21.9 | 26 | 29 |
 Lich | Ghost Scepter | 21.9 | 29 | 35 |
 Hunter | Double Barrel Shotgun | 21.9 | 26 | 36 |
 Romantic | Double Barrel Shotgun | 21.8 | 29 | 36 |
 Creature | Fist | 21.7 | 26 | 29 |
 Golem | Fist | 21.7 | 26 | 29 |
 Builder | Ghost Scepter | 21.6 | 29 | 36 |
 Apprentice | Fist | 21.6 | 26 | 29 |