In my first playthrough of Rome: Total War I was moving 2 equites (light cavalry) units between cities somewhere up in the barbarian wastes of Germania. Routine stuff, just a turn or two to trot between cities. But then (with me not even knowing ambushes existed in the game) a bunch of hairy-arsed axe-wielding Germanic nutters jumped out on my horsies, and I was in a battle I couldn't decline. So off we go to the battle screen: me 2 light cav as stated, them 4 BIG units of axemen (or about 100 v well over 300, to put it another way). I thought I had no chance, but I knew I had an edge in mobility so I gambled on that. I took my guys as far back to the edge of the battlefield as possible, in the corner, to make his units have to walk all that way; and then I waited until he was just about in charging range before bolting my horses at full speed 90 degrees to the next corner of the battlefield. There I waited, resting my guys while he just kept on trudging along behind. I did the same trick again, and again and again and again. Eventually even my horses where getting tired, so on the next encounter I fled to the middle of the battlefield instead of a corner. When he came after and got in range, I sped my two units off in opposite directions. After a little indecision he sent all his guys after one of my units, so I sprinted that one as far as possible while the other waited, now behind the enemy. The Germans were all exhausted by now, so I decided it was time for action - I slammed my resting equites into the back of the nearest baddies, and they broke in a second. I normally run down and destroy all enemies, but this was not that sort of day - I accepted that win and let them run off the field. Now 3 v 2, about 250 of them left. When I'd attacked, they'd turned all their forces back towards the battle but his unit broke so quickly (mostly from exhaustion I guess) they had no chance to pile into me - I walked my horses back away from them, keeping their interest. All this time my first unit had been resting, positioning himself, and now they had turned their backs to him it was his turn. Again, hard charge=instant break - another unit flees in terror. Now 2 v 2, probably 100 v 150+ - I had lost a very few, but I was still in the fight. In the end it was a simple flanking move that finished it - I sent cav out wide, one to each flank, and whichever axemen turned the wrong way got run down. That last engagement was brutal and I lost quite a few more, because I was still inexperienced and didn't realise the value of charging in and out repeatedly; I should not have stood and fought like I did. But they were exhausted and demoralised, and when I finally killed their leader they panicked and ran. I couldn't believe I'd survived that one. My commander that day was promptly adopted into the family and became a leading general; I was fanatically devoted to him from that day on, and gave him all the best commands and units. In fact by the time I completed the game he was faction heir.
Best of all - and again, as a new player I didn't know this and wasn't expecting it - when I got back to the campaign screen there was an icon marking the site of the battle, forever recording his outstanding heroic victory. I was delighted by that.