Northern Paladin could simply destroy target black permanent for just two White Mana, while Angry Mob has 2+*/2+*, where * was equal to the number of Swamps your opponent controlled
At MTG Decks & More we have over 50 years combined experience playing games including D&D, MTG, and dozens of other table and board games
And you'll gain life equal to what was lost, so in a four-player game with 5 black pips, your foes will each lose 5 and you'll gain 15
The loss of life might come from the effect of a mana ability causing you to be dealt damage (such as the last ability of Adarkar Wastes) or from the cost of a mana ability requiring you to pay life (such as the ability of Mana Confluence)
The deck has excellent reprints, with standouts being Clever Concealment, Skullclamp, Lightning Greaves, and Sword of the Animist