Reassessment:
This game is engaging, it is addictive, it is fun.
The game and its controls (literally WASD) are easy to pick up on, and within a few minutes, you find yourself spending more time playing, It encourages you to keep going every time you level up, and even after you "end the game" you want to "keep going".
It seems easy in the beginning, however don't let that put you at ease. This game still poses a challenge, wave after wave of entities trying to surround you. However, not something you would "rage quit" on.
I would like to say this game is both original and unique. (But I can't)
I've seen many games on mobile platforms in similar style: you move around, level up, neutralize enemies, upgrade, repeat. However, "other games" don't try to send "The Big Boss" with zero chance of defeat.
The artwork is good, soundtrack's good.
The sound effects in game catch my attention, adds some enjoyment when I play this game. (Who could miss the sound of a Lightning Bolt??) VO actress makes an OK cat noise, I completely missed on whether if she had any other roles within the game (apart from her sprite)
It fits the theme well.
I had nothing to say about this section, but the 'Big Boss Ludwig' definitely ensures you don't make it past 10 minutes, so I would say, yes, you could finish it under that time.
The font style options broke mid-way typing the review. RIP