this is normal, and the way all projectiles work in ToME.
First, your projectile need to have energy when you create it, otherwise it won't act until it has enough energy.
Second you need to ask it to act() after you're done instanciating it, otherwise even with energy it won't act until the next tick.
The most glaring in vanilla are called shots which say they're instant but are not despite having a huge amount of speed, and coupled with their weird targeting make them miss enemies more often than they hit.
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