GameConcept
Currency
Trading
NPC-Trading
Player
Health
Equip
Armor
Armor Classes (Ranger, Mage,...)
Weapons
Reforging
Random Rolls
Custom Look/Bullets/Animations/etc.
Levelling
Useable Equip
Stats increase
Customization
Generator
Armor display
Mobs
Levels
HP Scale
Attack Patterns
Bosses
Spawn depeding on...
Biome
Player level?
Day time
Player spawned
Buildable structures
Houses
Chests, Crafting tools/structures
Protectable
Public structures
Core
Buildable Blocks
Crafting
Mobs
Topdown 2D
Simplistic/ Pixely style
Engaging animations
Multi-level world
Multiplayer
Public servers
PVP / non-PVP
Guilds
No PVP in guild
Chat
Guild structures
Self-hosted servers
Custom settings
Procedural worldgen
Biomes
Dungeons?
NPC Cities?
Farmable resources
Mining
Ores
Different findables on different heights