Vidrik aims his shot perfectly at the skeleton's body, only to watch the crossbow bolt pass between the ribcage and pelvis, hitting nothing but air on its way through.
Chloe burns one of the oncoming zombies, and her animated servant damages the skeleton in front of Sabian.
The zombies advance forward, one walking onto the spikes, and another through the flames. The skeletal spellcaster behind advances, casting another spell. Grains of sand fall to the floor. Mustafar falls asleep, slowly dropping to the floor.
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Z2 is only prevented from reaching your line because Spike Growth is difficult terrain.
Spike growth damage to Z2 (2d4)[5]
Z3 bonfire (1d8)[4], Dex save (1d20-2)[4] to negate
SH casts Sleep. He's 90' away, but it has a 20' radius.
(5d8)[14] hp fall asleep, starting with the lowest and working upwards. Mustafar 3hp, Cassandra 10hp.... but elves are immune to magical sleep.
=>Sabian, Cassandra, Mustafar (asleep)