In Fallout, this weapon is very useful, capable of doing massive damage to clustered targets from a long-range. In Fallout 2 however, by the time the player finds the weapon and can access a consistent supply of ammo for it, they're likely near the end of the game, where enemies tend to wear power armor of some sort. Even then, the effective, yet oddly-designed armor piercing rockets it uses can slice through most Enclave contingents with one or two blasts. Most enemies, including deathclaws and aliens, have very little explosive resistance, making packs excellent targets. Using this on a locked door will destroy the door allowing you to walk through it.
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