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The edible blood could just be approx a 3:1 ratio of hershey's strawberry syrup to chocolate syrup, but buying capsules is still much better than making your own (we got away with this only because there was literally a cup to drink from).
Advantages and disadvantages (Grace Kane)
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The best option is to buy these. We tried to make them during HAMLET '17 and it didn't work very well - we ended up just having the actors drink the blood from a cup.
Costume stores/Garment District sells crappy ones that you have to spend a minute chewing to get the powder liquid enough to be realistic. This involves a lot of saliva/time before the pack is spat out.
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