Due to Reinforcement of the Armys ability to search such a large cardpool at a time when searching was a relatively rare effect, the deck was able to maintain relevance
If this card is in your GY: You can target 2 face-up cards in your Spell & Trap Zone
the turn it was set to search Rescue-ACE Preventer Preventer banish Hydrant to summon itself Preventer + Laevateinn = Promethean, activate Preventer to bring back Monster originally in hand Promethean effect, bring back Laevateinn Promethean + Monster originally in hand = Arbitrator Activate Arbitrator, add HQ Activate HQ, use effect to shuffle monster originally in hand, EMERGENCY!, ALERT!, and Turbulence to deck and draw 1 Ends on: Rescue-ACE Arbitrator + Laevateinn the Burning Blade + Rescue-ACE Hydrant + RESCUE
All of them accomplish our basic combos and bring other effects to the table, such as gaining LP, cycling a card from the hand, inflicting damage to the opponent, or sending a Prank-Kids card to the GY