Normal Variables:

Variable	Modifiable
meta_location_x	true
meta_location_y	true
meta_location_z	true
meta_location_pitch	true
meta_location_yaw	true
meta_saturation	true
meta_experience_level	true
meta_experience_points	true
meta_remaining_air	true
meta_max_air	true
meta_fly_speed	true
meta_walk_speed	true
meta_food_level	true
meta_entity_id	false
meta_fire_ticks	true
meta_fall_distance	true
meta_players_online	false
meta_max_health	true
meta_current_health	true
meta_health_scale	true
meta_compass_target_x	true
meta_compass_target_y	true
meta_compass_target_z	true
meta_velocity_x	true
meta_velocity_y	true
meta_velocity_z	true
meta_no_damage_ticks	true
meta_max_no_damage_ticks	true
meta_last_damage	true
meta_sleep_ticks	false
meta_bed_location_x (respawn location before 4.0 Beta 14, bed sleeping in since)	true before 4.0 Beta 14
meta_bed_location_y (respawn location before 4.0 Beta 14, bed sleeping in since)	true before 4.0 Beta 14
meta_bed_location_z (respawn location before 4.0 Beta 14, bed sleeping in since)	true before 4.0 Beta 14
meta_altitude	false
meta_absorption	true
meta_timestamp_days	false
meta_timestamp_hours	false
meta_timestamp_minutes	false
meta_timestamp_seconds	false
meta_timestamp_milliseconds	false
meta_mana	true
meta_max_mana	true
meta_mana_regen	true

Since 4.0 Beta 14:

Variable	Modifiable
meta_freeze_ticks	true
meta_max_freeze_ticks	false
meta_max_fire_ticks	false
meta_forwards_movement	false
meta_sideways_movement	false
meta_respawn_location_x	true
meta_respawn_location_y	true
meta_respawn_location_z	true
meta_exhaustion Hunger Mechanics	true
meta_starvation_rate Hunger Mechanics	true
meta_saturated_regen_rate Hunger Mechanics	true
meta_unsaturated_regen_rate Hunger Mechanics	true

Attribute Meta Variables:

There are two types per listed attribute: a modifiable type referring to the base attribute value before modifiers are applied and following the format meta_attribute_<attributeName>_base; and an unmodifiable type following the format meta_attribute_<attributeName>, which only returns the value of the attribute after all modifiers are applied. In either case <attributeName> should be the lowercase attribute name, with . separators replaced with _ (e.g. generic.armor_toughness -> generic_armor_toughness -> meta_attribute_generic_armor_toughness(_base)). Find attribute names and their min and max values here.

Since 4.0 Beta 14:

All linked attributes existing in your server version have a meta attribute variable associated with them.

Before 4.0 Beta 14:

Only the following attributes meta-variable exist:

• meta_attribute_generic_max_health(_base)
• meta_attribute_generic_follow_range(_base)
• meta_attribute_generic_knockback_resistance(_base)
• meta_attribute_generic_movement_speed(_base)
• meta_attribute_generic_flying_speed(_base)
• meta_attribute_generic_attack_damage(_base)
• meta_attribute_generic_attack_knockback(_base)
• meta_attribute_generic_attack_speed(_base)
• meta_attribute_generic_armor(_base)
• meta_attribute_generic_armor_toughness(_base)
• meta_attribute_generic_luck(_base)