[HJ]

If you're talking abut SP, you'll have little to worry about from Jotuns usually. They require a lot of supplies, and the AI is somewhat lacking in handling that. If you play a decent size map, chances are that most of them apart from those guarding the capital are going to be diseased by the time you reach them.

Other than that, try to swarm them with superior numbers. They'll win a 1 on 1 fights against most troops, but if you have superior numbers it means that you'll be able to get many attacks per single giant in a round, and their defense drops down with each subsequent attack. Since only one giant can fit into a square, you'll get something like 3 attacks per his one (3 humans fit in the square), and some of those attacks will land. Their size also means that missiles are more likely to hit them if they hit the square they're in. In other words, they hit hard, but are also relatively easy to hit. This is of course just a basic strategy without any magic or anything sophisticated, but it still works nevertheless.