Magic Archery (very short and solid incremental, free and unmonetized, very rare)

If you like incrementals look at the Gnorp Apologue. Very well designed and the presentation is top tier. Good enough to have spawned new 'Gnorp-like' games:

Dwarf Eats Mountain is very gnorp-like, it just released so the balance is a little rough but the dev is very active (there's been 4 updates in the past 3 days).

Journey to Incrementalia same idea, it does a good job on having unique troop 'builds' due to the synergies between different types of units and the prestige upgrades.

Honorable Mention: Tower Wizard, more standard incremental but well done.