For a Base Set card, Gyarados is pretty powerful with 100 HP, Dragon Rage (which does 50 points of damage) and Bubble Beam, which inflicts 40 points of damage and has the chance of Paralyzing the opponents Pokemon too
Mana Leak (7) and Memory Lapse (7) and even Unsubstantiate (7) are likely all better than Actual Counterspell (6.5) as colour intense spells are often pretty uncomfortable
Chaos Orb can destroy any permanent that it touches, along with itself, once the physical card is flipped like a coin over the table
Mixing rowdy kids with access to handfuls of peanuts did not make for the easiest magic performing environment
Additionally, its activated ability serves as its own payoff, allowing you to do serious damage and gain a nice amount of life
The full texts of these abilities are "At the beginning of the monarch's end step, that player draws a card" and "Whenever a creature deals combat damage to the monarch, its controller becomes the monarch." If the triggered ability that causes the monarch to draw a card goes on the stack and a different player becomes the monarch before that ability resolves, the first player will still draw the card