This beast would charge furiously at Beethro. Here's how it behaves:
It moves just like a roach, until
...until Beethro steps into Beast's line of sight. (Diagonally, vertically, horizontally).
It doesn't work if there's any obstacle (square other than floor tile or trapdoor tile).
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When it happens, the beast starts charging in direction of Beethro. It doesn't turn at all, and stops only if hits something.
If something = ....
Beethro - the beast stops and Beethro dies.
Wall - the beast stops, and continues to move like a roach... or immediately charges again, if Beethro is in the line of sight.
Closed door - same as above.
Force Arrow - depends on direction, if it's compatible the beast passes. If not, the beast stops.
an orb - the beast stops, but the orb is is hit, just like with sword !
crumbly wall - the beast stops, but crumbly wall square is destroyed.
a pit - the beast falls into it and dies.
non-serpent monster - the monster is killed, and the beast stops.
(the beast stops if hits a serpent)
(if two beasts charge at each other, both of them die !)
Tar - works just like hitting tar with a sword, but Beast stops anyway (regardless of tar being harmed or not)
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