Both of these skills can be used during combat with a cooldown:
Thunder Bolt deals a set amount of damage based on the skill level (starting at 20, +7 damage per level) with a cooldown of 20 seconds.
Invulnerability makes you immune to all damage for a set amount of time based on the skill level (starting at 3 seconds, +3 seconds per level) with a cooldown of 30 seconds.
You can upgrade your skill after choosing it for a gold cost. Each upgrade costs 500*skillLevel*skillLevel+500 gold bars, with no ceiling on the skill level.
Best Answer
Yes, your shovel can break in the process of digging a hole, and you may need to replace it to dig further holes.