Freebase Dali

When you're at lower levels, the best way to kill Giants is by climbing onto something they can't, like a pile of rocks that puts you out of the way of their weapon, and simply hit 'em with arrows at longer distances, and whatever destruction magic you have when they're bumbling around in the navmesh that doesn't let them navigate rocks.

If you don't have any handy terrain to keep you out of reach and they close the gap too quickly when you're on flat terrain, just avoid them until you're more powerful. They won't attack unless you get right up on them, so realistically, you shouldn't need to worry about them until you're strong enough to take them out easily. Whatever you do, though, your best bet is ranged weaponry, because unless your armor is very high, they're still going to knock you senseless very quickly.

This same strategy is useful for pretty much any creature that doesn't utilize projectiles. For example, if you know you can't take out a troll very easily and you stumble into one, your first reaction should be to flee and survey the area for collision objects like rock mounds and difficult-to-navigate terrain where it will be safer to attack. The navmesh for creatures and NPCs is generally laid out in such a way where they'll usually traverse direct routes and basic, flat terrain (which is why your follower usually never takes the more daring shortcuts you take).

A trick that comes in handy when trying to jump onto rock mounds and such terrain is, if jumping forward isn't working, turn around and jump backwards up rocks or out-of-travel areas like sides of mountains. Doing this while strafing side to side reveals gaps in the "invisible walls", letting you jump onto objects you wouldn't have been able to otherwise. In these areas, there is no navmesh on which NPCs can travel, and you are effectively shielded from their advance, giving you an opportunity to focus on your attack.

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