It's the first Neal Adams X-Men story.
The X-Men and Alex Summers are in Egypt with the Living Pharaoh captured, inside an archaeological site. Suddenly, a group of Pharaoh's guards appears, stuns the X-Men, releases his master and captures Alex. Angel goes behind them, and discovers that the Living Pharaoh wants to use Alex powers to increase his own mutant powers. Warren tries to warn the others, but it's too late, because the Pharaoh has already become The Living Monolith - a giant made of rocks. When he is almost defeating the X-Men, Alex uses his powers and destroys the whole temple. At the end, the Pharaoh is back to normal and Alex can't control his powers.
Second Story: "The flying A-Bomb"
Cyclops and Iceman are trying to convince Angel to join the X-Men. The Angel knocks down Iceman, and Professor Xavier mentally stops the fight to tell Warren that the vial he had stolen from thieves (last issue) is an A-Bomb ready to explode. Then the Angel flies so high that the vial freezes and he could break it. Finally, the Angel joins the X-Men.