Good idea:
Asking the thief to check out the passage ahead of you for traps.
Bad idea:
Insulting the thief and then asking him if the passage ahead of you is trapped.
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Good idea:
Casting fireball to destroy the waves of goblins rushing you.
Bad idea:
Casting fireball at the waves of onrushing goblins in a 20x20 room.
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Good idea:
Lining up your fighters shoulder to shoulder to cut down the line of kobolds
Bad idea:
Forgetting to make sure there's not an invisible mage with a lightning bolt off to your right just waiting for the fighters to line up shoulder-to-shoulder.
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Good idea:
Dimension dooring next to a line of pole-arm bearing goblins to hit them with a cone of cold.
Bad idea:
Casting the cone so that it misses the one right next to you.
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Good idea:
Pulling the pin and throwing the grenade at your enemies.
Bad idea:
Forgetting to make sure that the bullet-proof window between you and the enemy is open before throwing the grenade.
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Good Idea
Charging round a corner with an elephant gun after a mad occultist.
Bad Idea
Charging round a corner with an unloaded elephant gun after a mad occultist.
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Good Idea
Climbing a tree to avoid a Monster.
Bad Idea
Climbing a tree in Plate Armor to avoid a Monster and falling on your back.
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