The insta-death pits can be abused most easily, and having too many of these can make for a short (and lopsided, depending on the cohort) game.
The game mechanics allow for a lot of potential house rules, which on one hand is really good but sometimes I prefer a fair amount of structure.
I think for a 30" arena more than 3 insta death pits would be overkill.... If they were evenly spaced it would give only 10" spaces between pits, and with really mobile gladiators that is more than enough to ensure fairly consistent access to insta-death options
I think 1 or 2 pits will be the basis of my play testing for now...
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