http://imgur.com/1EY1fMD
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Looks like 1 golem 6-7 wiz to bracket troops rest witches CC golem 2 jump 2 rage from bottom up would do the trick with decent hero lvls. Use one jump to get in core and one to get out.
Just make sure golems are placed to distract the splash while witches get skellies up and running.
You can youtube videos of how to 3 star the turtle base as well as it looks like a modification of that base if you want to see other options for that base.