head to head
Stronghold HD asks more than Portal, and the gap is reads.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.

Optimization · Pure Optimization
Castle economy and siege engineering with light real-time micro.
Portal leans Optimization (Pure Optimization); Stronghold HD leans Optimization (Pure Optimization).
Portal leans a little harder on execution, though the gap is small.
Portal
Portal placement timing modest.
Stronghold HD
Real-time micro matters in sieges but stays modest
Stronghold HD leans clearly harder on reads.
Portal
No adversary modeling player.
Stronghold HD
Multiplayer sieges reward predicting human attack angles
Stronghold HD leans clearly harder on variance.
Portal
Deterministic chambers; no randomness.
Stronghold HD
Campaign events scripted; small skirmish unknowns
Portal leans a little harder on optimization, though the gap is small.
Portal
Pure puzzle-solving optimization.
Stronghold HD
Castle economy and siege engineering are the dominant layer
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.