It is possible to kill the Sidehoppers damageless by jumping into the bottom left corner then quickly spin jumping again.

Requires:

"ScrewAttack"
{
  "or": [
    "canCarefulJump",
    {
      "enemyDamage": {
        "enemy": "Sm. Sidehopper",
        "type": "contact",
        "hits": 1
      }
    }
  ]
}

Clears obstacles: A