Arena mode would crash if you examined monsters.
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BC24BZTIVJ6GORK7XXGHQ7YXKYBEPFCTKVCANZE6PEXY4L3ZQMCAC
K2CS6TCX2NDVL2ASEHGP4J4K4IJ6FP3ANNKTSIWVG43HPYSBX6ZQC
if (_blocked_ray(mon->pos(), &blocking_feat))
if (!crawl_state.arena_suspended && _blocked_ray(mon->pos(), &blocking_feat))
if (!crawl_state.arena_suspended
&& _blocked_ray(mon->pos(), &blocking_feat))