Generate a skill tree progression and economy model for an action survival game. Core Loop: The player spends 'Stamina' to perform actions: 'Gather Resources', 'Defeat Enemies', and 'Open Chests'. These actions generate 'Experience Points (XP)'. Stamina regenerates slowly over time. Conversion: Every 1000 XP automatically converts into 1 'Skill Point'. Skill Tree Economy: The player spends Skill Points to unlock nodes. There are 3 main progression branches: 'Combat' (increases damage output, making enemy kills faster). 'Survival' (increases max Stamina and Stamina regen rate). 'Crafting & Exploration' (increases resource drop rates from chests and environment). Scaling: The first node costs 1 Skill Point. Each subsequent node in a branch costs 1.5x more than the previous one. Goal: Simulate the player's journey to unlock the first 20 nodes, showing how the increased Stamina regen and damage output speed up their XP gathering over time.
