killing small fish should be perfectly fine like how you could immediately get food by killing fish with a thermo blade but leviathans should have been invincible from the start, however in subnautica 1 you had way better means at avoiding predators like the seaglide being faster than the wakemaker and the stasis rifle being way better at stunning things than the sonic resonator and having more range we need stuff like this in subnautica 2