Fat Burner · computed from the label

Instant Knockout

Name: Instant Knockout
Brand: Roar Ambition

by Roar Ambition · $65.00 / 30 servings ($2.17/serving)

Formula

Underdosed

Deal

Fair premium

✓ Worth it — a fair deal on a real formula

"Fat burner used by pro fighters." 4 capsules a day — full label, every dose disclosed.

2 of 6 recognized ingredients hit their clinically studied dose.

Ingredients vs the studied dose

Ingredient	Label dose	Status
Caffeine Anhydrous 300mg caffeine — a strong, effective dose (across 4 caps)	300mg	✓ OK
Vitamin D3 1,800 IU vitamin D3 — near the 2,000 IU target	1800 IU	✓ OK
Glucomannan 1.8g glucomannan — short of the 3g used for satiety/weight	1800mg	⚠ LOW
Green Tea Extract (EGCG) 500mg green tea = ~225mg EGCG, below the ~400mg fat-oxidation dose	500mg (45% EGCG)	⚠ LOW
L-Theanine 100mg L-theanine — half the 200mg that pairs with caffeine	100mg	⚠ LOW
Cayenne Pepper 100mg cayenne — present, but the thermogenic effect is small (experimental)	100mg	✓ OK

Make it yourself — per serving

Ingredient (bulk)	Cost/serving
Caffeine Anhydrous	$0.08
Vitamin D3	$0.04
Glucomannan	$0.27
Green Tea Extract (EGCG)	$0.15
L-Theanine	$0.02
Your DIY cost	$0.56
Roar Ambition charges ($65.00 / 30 servings)	$2.17

That's a 3.9× markup over building the same actives from bulk powders.

The verdict

Fully disclosed, so we grade the real numbers. The part that matters most — caffeine — is well dosed, alongside a real glucomannan fiber load and vitamin D. But the green-tea EGCG, theanine and glucomannan all land below their studied doses, and cayenne's thermogenic effect is marginal. A reasonable, honestly-labeled formula that's badly overpriced: the working parts are cheap staples.

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Educational only — not medical advice. Grades and clinical doses are computed from public labels against sourced research (citations on the main site); prices last verified 2026-07-21. Expensive Powder has no sponsors; bulk links may earn an affiliate commission, which never affects a grade. Talk to a clinician before starting any supplement.