Need at least 2 poison members to clear stage 4 and 5. Leaders should be a monster with sturdy and a healer. Basically make sure your poison skill is ready by the 4th stage. If you have 4 poison, just get your skills up at stage one and breeze through the rest.
Best setup is green orge and 4x lvl2 FF flowers (with a healer), because they basically incorporate strat 3 into this strat, making it a sure-fire way to clear the stage.
That was hell of a poison set-up if the game has PVP that might be interesting one lol
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