He was infamous for his "Charge of the Horde" tactic which postulated that large numbers of small, individually weak BattleMechs could overwhelm more powerful 'Mechs through sheer numbers. To this end he suggested forming "hordes" of six to ten light 'Mechs, preferrably Stingers and Wasps, instead of the traditional lances. He reasoned that these could be built relatively cheap and easy, and deploying them in large numbers would also make it easier to repair and maintain them. Furthermore, most damage was expected to be relatively light and thus most casualties would be damaged 'Mechs that could be repaired.
Driven by fanaticism, Tai-i Ravannion led several such swarming attacks without regard for men or material, invariably suffering disastrous defeats. Despite these military setbacks, he insisted that his tactics were sound. Known instances include:
- Defending Fallon II against elements of the 7th Crucis Lancers in 3019, he led four Stingers and two Wasps (including his own) against the scout lance of McKinnon's Raiders at the Battle of Markerson, losing all six 'Mechs and escaping only after ejecting from his disabled 'Mech. The 12th Star Guards mercenary unit had been ordered to contribute a Stinger to the attack, and had sent a Shadow Hawk along as an impartial observer (and for safety), the only unit to survive the attempt. It was noted that no House was subsequently prepared to risk 'Mechs on his theories.
- In 3022 he attacked Xhosa VII, where he unleashed hordes of Stingers and Wasps against the understrength planetary garrison which consisted of two companies of the Draconis March Militia equipped mostly with Locusts and Blackjacks. The attack was repulsed by the inexperienced, freshly graduated Cadet Captain Michael Ubodo who earned himself a decoration and demonstrated on the sidelines that even ill-reputed 'Mechs like the Blackjack can shine when used properly. Ravannion's troops retreated to their DropShips in disorder.
- In 3023, Ravannion was killed in another fight with McKinnon's Raiders on Fallon II.
Stinger pilot Marge Sippers served under Ravannion when she was 16 years old. Rumored to have a schoolgirl crush on her mentor, she rose to the rank of Tai-i herself after his death and redeemed the "Charge of the Horde" tactic by including somewhat heavier units, especially Jenners.
- Mercer Ravannion's obsession with an apparently hopeless tactical theory and his frequent defeats border on comic relief and have made the character popular among BattleTech fans.
- Technical Readout: 3025 mentions Tai-i Ravannion in two separate entries (for the Stinger and Blackjack, respectively) and gives the distinct impression that Ravannion's "Charge of the Horde" is an unsound tactic; similarly, the book's entry for the Atlas treats claims that a single Atlas could defeat an entire battalion of Stingers as credible. However, despite the descriptions ridiculing Ravannion's theory, it should be noted that game mechanics appear to prove him right: "Charge of the Horde" tactics (also known as "swarming") do in fact have merit under regular boardgame rules, where they are quite effective.
- Technical Readout: 3039 repeats most of the text from TRO: 3025 and calls Ravannion's theories "discredited". It also mentions Tai-i Sippers and how she achieved surprising victories using the Charge of the Horde with Jenners. However, it should be noted that this considerably dilutes the original concept: at 35 tons, Jenners are almost twice as heavy as Ravannion's preferred 20-ton 'Mechs and significantly more powerful (being noted as a particularly heavily armed design) but also considerably more expensive, defeating the original premise of the "Charge of the Horde" as a way to make use of individually weak but cheap units.
- Technical Readout: 3025, p. 8 (Stinger entry)
- The Fox's Teeth, pp. 14-15
- Technical Readout: 3025, p. 48 (Blackjack entry)
- Technical Readout: 3039, pp. 112, 282