From Brotato Wiki
Upgrades
Upgrades are stat improvements that happen at each level up. Luck affects the rarity of upgrades. However some levels have 100% rarity rates:
- Level 1: 100% Tier 1
- Level 5: 100% Tier 2
- Level 10: 100% Tier 3
- Level 15: 100% Tier 3
- Level 20: 100% Tier 3
- Level 25: 100% Tier 4
- Every 5th level after: 100% Tier 4