Not by default Shane, but if your GM creates custom fx, you can try some things. Here's a kinda crummy rock effect (the gm would have to create it in game, I think fx are pro only to make and have work in games, though anyone in the game can use them): {
"maxParticles": 1,
"emissionRate": 1,
"size": 15,
"sizeRandom": 1,
"lifeSpan": 30,
"lifeSpanRandom": 1,
"speed": 50,
"speedRandom": 1.5,
"gravity": {"x":0.01, "y":0.01},
"angle": -1,
"angleRandom": 1,
"duration": 1,
"startColour": [50, 50, 50, 1],
"startColourRandom": [10, 10, 10, 0.1],
"endColour": [50, 50, 50, 1],
"endColourRandom": [10, 10, 10, 0.1]
}