I’m thinking of a game which was on a site called towerdefence.net, or something very similar, which went down a year ago or two.
It was an vertical column, and you placed your units at the bottom. They would charge upwards, at the enemy’s units. At the very bottom of the screen, you had your champion, who could cast spells, and the enemy champion at the top also cast spells. You had to defeat their champion to win. You lost, of course, if yours was defeated.
I remember the enemy units often being skeletons, and think your units were things like wizards, archers, swordsmen.
There may’ve been a necromancy theme, possibly with a bad guy or the game itself being called necro-something.
Any help appreciated.