Streets of Rage 4 (SOR4) has many different trophies and achievements that you can unlock, one of which is Collateral Damage. Collateral Damage is a trophy achievement that requires you to use a barrel or a grenade explosion to kill 3 enemies at the same time.
If you manage to unlock this you will obtain a Bronze trophy and/or 15 Achievement Points
This trophy achievement can be unlocked during Stage 3 – Cargo Ship, whilst on this stage if you continue on as normal, you should encounter your first barrel. As long as you haven’t killed everyone yet you should also have a few enemies around too, if so then we should be good to continue..
You will now need to wait until you are literally surrounded by enemies, well you ideally just need to have at least 3 enemies around but to be safe I would recommend that there where more than 3.
When you are surrounded by enough enemies, you will then want to attack the explosive barrel until it explodes.
It is that simple and since using a Grenade is optional, you will still get the trophy achievement even if all you did was destroy a single barrel. BOOOM!
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