head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Optimization · Pure Optimization
Tower-defense loadout math wearing an Adventure Time crossover costume.

Optimization · Pure Optimization
Lane defense classic about managing a sun economy against shambling waves.
Bloons Adventure Time TD leans Optimization (Pure Optimization); Plants vs. Zombies leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Bloons Adventure Time TD
Tower placement and occasional ability taps
Plants vs. Zombies
Clicking to plant, minimal pressure
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Bloons Adventure Time TD
Bloon rushes follow fixed wave scripts
Plants vs. Zombies
Zombie waves follow set compositions
Plants vs. Zombies leans a little harder on variance, though the gap is small.
Bloons Adventure Time TD
Character trinket drops add light collection RNG
Plants vs. Zombies
Wave timing and lane pressure vary mildly
Plants vs. Zombies leans a little harder on optimization, though the gap is small.
Bloons Adventure Time TD
Hero, allies and trinket loadout math drives every map
Plants vs. Zombies
Sun economy and lane setups are near-solvable
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.