Example Particle

[gd_scene load_steps=8 format=2]

[ext_resource path="res://round.png" type="Texture" id=1]

[sub_resource type="CanvasItemMaterial" id=1]

[sub_resource type="Gradient" id=2]
offsets = PoolRealArray( 0, 0.523077, 1 )
colors = PoolColorArray( 1, 1, 1, 1, 1, 0.793945, 0.175781, 1, 0.742188, 0.0579834, 0.0579834, 1 )

[sub_resource type="GradientTexture" id=3]
gradient = SubResource( 2 )

[sub_resource type="Curve" id=4]
_data = [ Vector2( 0, 0.0677118 ), 0.0, 0.0, 0, 0, Vector2( 1, 0 ), 0.0, 0.0, 0, 0 ]

[sub_resource type="CurveTexture" id=5]
curve = SubResource( 4 )

[sub_resource type="ParticlesMaterial" id=6]
flag_disable_z = true
spread = 180.0
gravity = Vector3( 0, 0, 0 )
initial_velocity = 4.0
angular_velocity = 5.82818e-010
orbit_velocity = 0.0
orbit_velocity_random = 0.0
scale_random = 0.04
scale_curve = SubResource( 5 )
color_ramp = SubResource( 3 )

[node name="Particles2D" type="Particles2D"]
material = SubResource( 1 )
position = Vector2( -0.174824, -0.0553246 )
amount = 50
lifetime = 0.7
local_coords = false
draw_order = 1
process_material = SubResource( 6 )
texture = ExtResource( 1 )