SCRAM makes Half-Life more difficult. To balance the difficulty, SCRAM adds goals and rewards in each Half-Life map.
The core Half-Life game is intact in SCRAM. To be clear, this is a new way to play through the standard single player portion of Half-Life.
But this time enemies are tougher, smarter, and faster. To survive you might come to depend on reaching the 3 lambda nuclei scattered in each level. Find one and you might be rewarded – find two or all three and you’ll definitely get a nice gift at the end of the level.