You can't really "rely" on Celestials, not at 20 gems/summon.
Celestial Masters aren't cheap, but they're a pretty good deal for what you get.
Magic Duel is an issue, but consider: you're not really facing any astral powers, unless you want to count Abysia. 1 in 8 Warlocks will have S3, but at 270 gold a pop, he isn't likely to have many Warlocks running around. If you really fear Magic Duel, you can always have your Wyrm go to sea or retire to the lab after his initial bout of indy conquering...
Oh, and if its banishing you're after - use the Masters. Nothing like a quickened level 3 preist with good accuracy for smiting undead swarms
Re: Help needed for challenge game
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