Most enemies are just things to avoid (lacking interplay). When I see enemies I don't get exciting to avoid them or take them out.Most enemies were built around the idea that they are not aggressive, but still dangerous. This is built deep within the genome of Bilou's world: there is no invasion army we fight against, rather wild beast not appreciating that you disturb their business. Yet, it turns out that for a time attack side-scroller, we're missing something that would have wider range and somewhat chase Bilou (60px/sec when walking). I needed something that's mostly on the ground and dismissed with primary mechanic, but that moves faster than pendat (16px/sec) or dumblador (8px/sec).
Making Pendats Run?
That would be the easy way out. or should be. Design documents from 2004-2005 show pendats that charge Bilou with their spears. Even earlier, the comic show them knocking down stacks of books. Yet, this is hard to achieve -- if ever possible -- with today's pixel art pendat. To reach that, I will need the hybrid vector/bitmap animation editor I intended to use for BangBash.
Bangbash wouldn't help.
He's more than just dangerous. He's dangerous and quick to anger. Maybe that's not yet what makes you excited about facing an opponent, but at least, that should build up some tension.
Something a la Blues Brothers ...
That game from Titus is one where I could feel engaged in dispatching enemies. They weren't very developed, either shooting, wandering or wandering-and-shooting-if-spotting-you, but they were moving about as fast as yourself. If they weren't as smart as the pendat described above, they'd usually have a "knock you down" animation when they hurt you. They're also quite fast. If you find yourself out of crate, think twice before you revert direction because every pixel between you and the bad guy count. You won't outrun them as easily as a goomba.
So if you haven't guessed from the size-test picture, I'm opting for a staple remover. These things look hazardous enough in real-life, it's not a wonder why you can find some customized into T-Rex heads. I've endured countless buzzing of Nintendo's "Donkey Kong Jr." game-over as I got my feet chunked into bits by those living wolf traps and their klap trap derivative. It doesn't turn very easy to pixel, however.