Hopefully not too late to this. Ended up in a battle limited to melee monsters and either light or death monsters, so it seemed like a perfect sand worm opportunity.
Here's the full battle (we both had similar ideas):
My approach assumed that we would both use Zintar so no need for anything over 1 melee except sand worm.
I also knew I wanted to ultimately have the sandworm and haunted spirit alive so I tried to place them in slightly more protected spaces (probably should have moved the worm up one more). The scorpion and slimeball just needed to soak up some damage while I thinned their backline a bit (if they had a heavy hitter in the first spot).
While I won, this was way closer than expected. One more miss by the sand worm (below) and it would have died, resulting in a loss or draw.