Avalon: Routine at 55068

Executed after 8 game timer cycles. Combined with a pseudo-random number, this affects the likelihood interval of a creature (spider/bat) appearing in the tunnel.

The room number is one of the variables in this calculation
There's a slightly lower chance of creatures appearing in higher numbered tunnel rooms
The room tunnel numbers (26384) start high and decrease for deeper levels within the game - e.g. interconnecting tunnel room numbers within the Gatehouse Level are 251-255
This means Maroc will tend to encounter more creatures within Avalon's deeper tunnels

Used by the routine at 54994.
Jump from 55008 if no new tunnel wall has been generated during this particular game cycle. Every 8 game cycles, there's a chance of a creature appearing.
55068	LD A,(60074)	Get the game timer
55071	INC A	Increment it
55072	AND 7	Check bits 0-2 (values 0-7)
55074	JR NZ,55188	Check bits 0-2 (values 0-7)
Executed after 8 game timer cycles. Combined with a pseudo-random number, this affects the likelihood interval of a creature (spider/bat) appearing in the tunnel. The room number is one of the variables in this calculation There's a slightly lower chance of creatures appearing in higher numbered tunnel rooms The room tunnel numbers (26384) start high and decrease for deeper levels within the game - e.g. interconnecting tunnel room numbers within the Gatehouse Level are 251-255 This means Maroc will tend to encounter more creatures within Avalon's deeper tunnels
55076	CALL 56070	Generate pseudo-random number in A register
55079	LD C,A	Store in C register
55080	LD A,(60087)	Get room number
55083	SUB 48	Because tunnels are rooms 224-255, this will result in a value somewhere in the 176-207 range
55085	CP C	Is this value greater than the random number?
55086	JR NC,55188	If so, jump out of here If not, continue to the next routine to generate a SPIDER or a BAT