Fuck, there is an issue with the save system. I'll work out what went wrong and do an update.
EDIT: Save System is fixed but old saves are F'd. If you wanted to continue to play you can either do the tutorial again or paste the text between the lines in following into the following path
C:\Users\{You}\AppData\Roaming\Godot\app_userdata\Healed To Death\saves\save01.tres
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[gd_resource type="Resource" script_class="SaveData" load_steps=2 format=3]
[ext_resource type="Script" path="res://Data/SaveData.gd" id="1"]
[resource]
script = ExtResource("1")
game_version = "0.7.0"
data = {
"CompletedLevels": ["LEVEL_TUTORIAL"],
"DiscoveredEnemies": Array[String](["ENEMY_SKELETON", "ENEMY_SKELETON_RENDER", "ENEMY_SKELETON_FIREMAGE", "ENEMY_SKELETON_TOXIC", "ENEMY_SKELETON_HEALER", "ENEMY_BOSS_FIREBONTLIEUTENANT", "ENEMY_BRITTLE_SKELETON", "ENEMY_BRITTLE_POISONER", "ENEMY_HOLLOWBONE_SKELETON", "ENEMY_BOSS_CROMWELL", "ENEMY_CROMWELLSERVENT", "ENEMY_BOSS_ARCANEMAGISTRATE", "ENEMY_BOSS_OSSIFIEDOVERLORD", "ENEMY_SKELETON_FRAIL", "ENEMY_SKELETON_ENRAGER", "ENEMY_SKELETON_FLAMEFIST", "ENEMY_SKELETON_GOLIATH", "ENEMY_SKELETON_SUMMONER", "ENEMY_SKELETON_TORTURER", "ENEMY_SKELETON_BATTLEMAGE", "ENEMY_SKELETON_STALWART", "ENEMY_SKELETON_DARKSTRIKER", "ENEMY_SKELETON_AVENGER"]),
"DiscoveredSpells": Array[String](["SPELL_HEAL", "SPELL_BIGHEAL", "SPELL_INSTANTHEAL", "SPELL_ABSORBTION", "SPELL_HEALOVERTIME", "SPELL_CIRCLEOFHEALING", "SPELL_CHAINHEAL", "SPELL_FLASHHEAL", "SPELL_HEALINGSTREAM", "SPELL_HOLYLIGHT"]),
"DiscoveredUpgrades": Array[String]([]),
"HealerPower": 0,
"PUDamageSlots": 3,
"PUHealerSlots": 1,
"PUTankSlots": 1,
"PermaCriticalStrikeUpgrade": 0,
"PermaHealthUpgrade": 0,
"PermaMagicalDamageUpgrade": 0,
"PermaPhysicalDamageUpgrade": 0,
"TownBarracksBuildLevel": 0,
"TownHallBuildLevel": 1,
"TownInnBuildLevel": 0,
"TownMonasteryBuildLevel": 0,
"UnlockedLevels": ["LEVEL_TOWN", "LEVEL_AREAGENERIC"],
"WorldGold": 200
}
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