Sorry, but I never found Death Star in this game. And I missed it. But I got Geyser maxed, and up to 10k on 8 units is not bad either
I also did not find Divine Armor, which gave me a huge challenge when fighting Baal. My standard lineup could not beat him. I managed to kill him to about 50%, but at that time the only remaining unit were the Trolls... So, I picked up a single stack of Cursed Ghost. They have 50% Physical Resistance. A Stone Skin on them + the medal got them to 95% physical resistance. The challenge was to ballance this stack. I started with the maximum of 284 units in one stack. I tried to never get the number below 150 and never above 250 during the fight. They regenerate when they eat up enemy units, and if they pass 284 it is immediate defeat. It was a long fight where most of the damage to Baal was done by spells. The cursed ghost did only 2000 in damage to Baal, which is pretty bad considering Baal's 270 000 hit points...