The water ball is a little drip. It only has one arm, so it can only attach below another ball.

<ball name="water"
      shape="circle,30"
      mass="30"
	  towermass="3.0"
      strands="1" 
      walkspeed="0.15"
      climbspeed="2.4"
      speedvariance="0.3"
      jump="0.0,0.1"
      detachable="false" 
      flammable="false"
      >
 
  <marker drag="IMAGE_BALL_WATER_DRAGMARKER_P1" 
          detach="IMAGE_BALL_WATER_DRAGMARKER_P1" 
          rotspeed="2"/>
 
  <shadow image="IMAGE_BALL_WATER_SHADOW"/>
 
  <particles id="sleepyZzz" states="sleeping" overball="true" />
 
  <strand type="rope" 
          image="IMAGE_BALL_WATER_STRAND" 
          inactiveimage="IMAGE_BALL_GENERIC_ARM_INACTIVE" 
          springconstmin="4" springconstmax="4" 
          dampfac="0.1" 
          maxlen2="130" maxlen1="130" 
          maxforce="800"
          minlen="120"
          rope="true"/>
 
  <detachstrand image="IMAGE_BALL_WATER_DSTRAND" maxlen="160" />
 
  <splat image="IMAGE_BALL_WATER_SPLAT1,IMAGE_BALL_WATER_SPLAT2"/>
 
  <part name="body"
        layer="0" 
        x="0" y="0" 
        image="IMAGE_BALL_WATER_BODY"
        stretch="10,2.5,0.7"
        scale="0.5"
        />
  <part name="lefteye"
        layer="1"
        rotate="true"
        x="-16,-11" y="-4,4"
        eye="true" 
        pupil="IMAGE_BALL_GENERIC_PUPIL1"
        pupilinset="13"
        image="IMAGE_BALL_GENERIC_EYE_GLASS_1,IMAGE_BALL_GENERIC_EYE_GLASS_2,IMAGE_BALL_GENERIC_EYE_GLASS_3"
        scale="0.5"
        state="climbing,walking,falling,dragging,detaching,standing,tank"
        />
  <part name="righteye"
        layer="1"
        rotate="true"
        x="11,16" y="-4,4"
        eye="true"
        pupil="IMAGE_BALL_GENERIC_PUPIL1"
        pupilinset="13"
        image="IMAGE_BALL_GENERIC_EYE_GLASS_1,IMAGE_BALL_GENERIC_EYE_GLASS_2,IMAGE_BALL_GENERIC_EYE_GLASS_3"
        scale="0.5"
        state="climbing,walking,falling,dragging,detaching,standing,tank"
        />
 
  <sound event="drop"      id="SOUND_BALL_GENERIC_MUMBLE1,SOUND_BALL_GENERIC_MUMBLE2,SOUND_BALL_GENERIC_MUMBLE3,SOUND_BALL_GENERIC_MUMBLE4,SOUND_BALL_GENERIC_MUMBLE5,SOUND_BALL_GENERIC_MUMBLE6,SOUND_BALL_GENERIC_MUMBLE7"/>
  <sound event="throw"     id="SOUND_BALL_GENERIC_MUMBLE1,SOUND_BALL_GENERIC_MUMBLE2,SOUND_BALL_GENERIC_MUMBLE3,SOUND_BALL_GENERIC_MUMBLE4,SOUND_BALL_GENERIC_MUMBLE5,SOUND_BALL_GENERIC_MUMBLE6,SOUND_BALL_GENERIC_MUMBLE7"/>
  <sound event="bounce"    id="SOUND_BALL_GENERIC_BOUNCE1,SOUND_BALL_GENERIC_BOUNCE2,SOUND_BALL_GENERIC_BOUNCE3,SOUND_BALL_GENERIC_BOUNCE4"/>
  <sound event="land"      id="SOUND_BALL_GENERIC_STICK1,SOUND_BALL_GENERIC_STICK2,SOUND_BALL_GENERIC_STICK3,SOUND_BALL_GENERIC_STICK4,SOUND_BALL_GENERIC_STICK5,SOUND_BALL_GENERIC_STICK6"/>
  <sound event="marker"    id="SOUND_BALL_GENERIC_ROLLOVER1,SOUND_BALL_GENERIC_ROLLOVER2,SOUND_BALL_GENERIC_ROLLOVER3,SOUND_BALL_GENERIC_ROLLOVER4,SOUND_BALL_GENERIC_ROLLOVER5,SOUND_BALL_GENERIC_ROLLOVER6,SOUND_BALL_GENERIC_ROLLOVER7,SOUND_BALL_GENERIC_ROLLOVER8"/>
  <sound event="pickup"    id="SOUND_BALL_GENERIC_PICKUP1,SOUND_BALL_GENERIC_PICKUP2,SOUND_BALL_GENERIC_PICKUP3,SOUND_BALL_GENERIC_PICKUP4,SOUND_BALL_GENERIC_PICKUP5,SOUND_BALL_GENERIC_PICKUP6,SOUND_BALL_GENERIC_PICKUP7,SOUND_BALL_GENERIC_PICKUP8,SOUND_BALL_GENERIC_PICKUP9,SOUND_BALL_GENERIC_PICKUP10"/>
  <sound event="attach"    id="SOUND_BALL_GENERIC_STICK1,SOUND_BALL_GENERIC_STICK2,SOUND_BALL_GENERIC_STICK3,SOUND_BALL_GENERIC_STICK4,SOUND_BALL_GENERIC_STICK5,SOUND_BALL_GENERIC_STICK6"/>
  <sound event="detaching" id="SOUND_BALL_GENERIC_DETACHING1"/>
  <sound event="detached"  id="SOUND_BALL_GENERIC_DETACHED1"/>
  <sound event="snap"      id="SOUND_BALL_GENERIC_SNAP1"/>
  <sound event="death"     id="SOUND_BALL_GENERIC_DEATH1"/>
  <sound event="suction"   id="SOUND_BALL_GENERIC_DETACHED1"/>
  <sound event="exit"      id=""/>
 
 
  <!-- attached animations -->
  <sinvariance freq="0.3" amp="0.02" shift="0.8">
    <sinanim part="body"             state="attached" type="scale"     axis="x" freq="1.2" amp="0.1" shift="0"   />
    <sinanim part="body"             state="attached" type="scale"     axis="y" freq="0.8" amp="0.1" shift="0.5" />
    <sinanim part="body"             state="attached" type="translate" axis="y" freq="1.4" amp="2"   shift="0"   />
    <sinanim part="lefteye,righteye" state="attached" type="translate" axis="y" freq="0.9" amp="2"   shift="0" />
    <sinanim part="righteye"         state="attached" type="translate" axis="x" freq="1.2" amp="0.5" shift="0" />
    <sinanim part="lefteye"          state="attached" type="translate" axis="x" freq="1.2" amp="0.5" shift="0.5" />
  </sinvariance>
 
  <!-- walking animations -->
  <sinvariance freq="1.2" amp="0.1" shift="0.0">
    <sinanim part="body"             state="walking" type="scale"     axis="x" freq="2.0" amp="0.1" shift="0"   />
    <sinanim part="body"             state="walking" type="scale"     axis="y" freq="2.0" amp="0.1" shift="0.5" />
    <sinanim part="body"             state="walking" type="translate" axis="y" freq="2.0" amp="2"   shift="0"   />
    <sinanim part="lefteye,righteye" state="walking" type="translate" axis="y" freq="2.0" amp="2"   shift="0" />
    <sinanim part="righteye"         state="walking" type="translate" axis="x" freq="2.0" amp="0.5" shift="0" />
    <sinanim part="lefteye"          state="walking" type="translate" axis="x" freq="2.0" amp="0.5" shift="0.5" />
  </sinvariance>
 
  <!-- dragging animations -->
  <sinvariance freq="0.3" amp="0.03" shift="0">
    <sinanim part="body" state="dragging" type="scale" axis="x" freq="1.0" amp="0.05" shift="0" />
    <sinanim part="body" state="dragging" type="scale" axis="y" freq="1.0" amp="0.05" shift="0" />
  </sinvariance>
 
 
 
  <!-- Sound FX -->
 
  <sound event="marker"       id="SOUND_BALL_GENERIC_ROLLOVER1,SOUND_BALL_GENERIC_ROLLOVER2,SOUND_BALL_GENERIC_ROLLOVER3,SOUND_BALL_GENERIC_ROLLOVER4,SOUND_BALL_GENERIC_ROLLOVER5,SOUND_BALL_GENERIC_ROLLOVER6,SOUND_BALL_GENERIC_ROLLOVER7,SOUND_BALL_GENERIC_ROLLOVER8"/>
  <sound event="pickup"       id="SOUND_BALL_WATER_DRIP01,SOUND_BALL_WATER_DRIP02,SOUND_BALL_WATER_DRIP03,SOUND_BALL_WATER_DRIP04,SOUND_BALL_WATER_DRIP05,SOUND_BALL_WATER_DRIP06,SOUND_BALL_WATER_DRIP07,SOUND_BALL_WATER_DRIP08,SOUND_BALL_WATER_DRIP09,SOUND_BALL_WATER_DRIP10"/>
 
  <sound event="drop"         id="SOUND_BALL_WATER_DRIP01,SOUND_BALL_WATER_DRIP02,SOUND_BALL_WATER_DRIP03,SOUND_BALL_WATER_DRIP04,SOUND_BALL_WATER_DRIP05,SOUND_BALL_WATER_DRIP06,SOUND_BALL_WATER_DRIP07,SOUND_BALL_WATER_DRIP08,SOUND_BALL_WATER_DRIP09,SOUND_BALL_WATER_DRIP10"/>
  <sound event="throw"        id="SOUND_BALL_WATER_DRIP01,SOUND_BALL_WATER_DRIP02,SOUND_BALL_WATER_DRIP03,SOUND_BALL_WATER_DRIP04,SOUND_BALL_WATER_DRIP05,SOUND_BALL_WATER_DRIP06,SOUND_BALL_WATER_DRIP07,SOUND_BALL_WATER_DRIP08,SOUND_BALL_WATER_DRIP09,SOUND_BALL_WATER_DRIP10"/>
 
  <sound event="bounce"       id="SOUND_BALL_GENERIC_BOUNCE1,SOUND_BALL_GENERIC_BOUNCE2,SOUND_BALL_GENERIC_BOUNCE3,SOUND_BALL_GENERIC_BOUNCE4"/>
  <sound event="land"         id="SOUND_BALL_GENERIC_STICK1,SOUND_BALL_GENERIC_STICK2,SOUND_BALL_GENERIC_STICK3,SOUND_BALL_GENERIC_STICK4,SOUND_BALL_GENERIC_STICK5,SOUND_BALL_GENERIC_STICK6"/>
 
  <sound event="attach"       id="SOUND_BALL_WATER_DRIP01,SOUND_BALL_WATER_DRIP02,SOUND_BALL_WATER_DRIP03,SOUND_BALL_WATER_DRIP04,SOUND_BALL_WATER_DRIP05,SOUND_BALL_WATER_DRIP06,SOUND_BALL_WATER_DRIP07,SOUND_BALL_WATER_DRIP08,SOUND_BALL_WATER_DRIP09,SOUND_BALL_WATER_DRIP10"/>
  <sound event="attachcloser" id="SOUND_BALL_GENERIC_GLEE1,SOUND_BALL_GENERIC_GLEE2,SOUND_BALL_GENERIC_GLEE3,SOUND_BALL_GENERIC_GLEE4,SOUND_BALL_GENERIC_GLEE5,SOUND_BALL_GENERIC_GLEE6,SOUND_BALL_GENERIC_GLEE7,SOUND_BALL_GENERIC_GLEE8,SOUND_BALL_GENERIC_GLEE9,SOUND_BALL_GENERIC_GLEE10,SOUND_BALL_GENERIC_GLEE11"/>
  <sound event="detaching"    id="SOUND_BALL_GENERIC_DETACHING1"/>
  <sound event="detached"     id="SOUND_BALL_WATER_DRIP01,SOUND_BALL_WATER_DRIP02,SOUND_BALL_WATER_DRIP03,SOUND_BALL_WATER_DRIP04,SOUND_BALL_WATER_DRIP05,SOUND_BALL_WATER_DRIP06,SOUND_BALL_WATER_DRIP07,SOUND_BALL_WATER_DRIP08,SOUND_BALL_WATER_DRIP09,SOUND_BALL_WATER_DRIP10"/>
 
  <sound event="snap"         id="SOUND_BALL_WATER_DRIP01,SOUND_BALL_WATER_DRIP02,SOUND_BALL_WATER_DRIP03,SOUND_BALL_WATER_DRIP04,SOUND_BALL_WATER_DRIP05,SOUND_BALL_WATER_DRIP06,SOUND_BALL_WATER_DRIP07,SOUND_BALL_WATER_DRIP08,SOUND_BALL_WATER_DRIP09,SOUND_BALL_WATER_DRIP10"/>
 
  <sound event="death"        id="SOUND_BALL_WATER_SPLASH01,SOUND_BALL_WATER_SPLASH02,SOUND_BALL_WATER_SPLASH03,SOUND_BALL_WATER_SPLASH04"/>
  <sound event="deathfall"    id="SOUND_BALL_WATER_SPLASH01,SOUND_BALL_WATER_SPLASH02,SOUND_BALL_WATER_SPLASH03,SOUND_BALL_WATER_SPLASH04"/>
 
  <sound event="suction"      id="SOUND_BALL_GENERIC_DETACHED1"/>
  <sound event="exit"         id=""/>
 
 
</ball>