Super Serum with some unpleasant side effects, most commonly insanity. The Psycho Serum could be the result of questionable government programs Gone Horribly Wrong or freak lab accidents; the user might be unaware of the side effects... or just doesn't care. Assuming, of course, that they actually consented to it in the first place. Consequences include, but are by no means limited to:
Recurring and persistent addiction.
Physical dependence.
Insanity.
Evil.
New appendages.
Anti-human tendencies.
Rebelliousness.
Murderous rage.
Deadly Nosebleeds.
Meltdowns.
Lower life expectancy.
Complete obedience to whoever administered it.
Harmful Healing.
Tainted Veins.
Torn clothes.
Since the idea is that it makes one more likely to be victorious (usually in battle) despite the above, it's closely associated with the concept of Race To The Bottom.
A form of Drugs Are Bad. Not to be confused with Power-Upgrading Deformation, where the ugly appearance is the cause of the superpowers, not a side effect. See also Bottled Heroic Resolve, when this trope is applied systematically. See Chemically-Induced Insanity for cases where causing insanity in the user was the whole point to begin with.
This item is available in the Trope Co. Catalog
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