Echo Chamber (EDH / Commander)

Kalamax is an odd one, and honestly might need more tuning. Opening hands are more inconsistent than in other decks, but the explosive potential is tempting. What's more, the deck only has a handful of creatures, making you an easy target for attack. What gives? The plan is to bide your time and strike when opportunity presents (ignore opportunity card pop-ups, it's not intentional). Keep Kalamax tapped using sources like Cultivator's Caravan, Survivors' Encampment, Holdout Settlement, or Cryptolith Rite; or by attacking into survivable combat. Since you only get a free copy of the first instant you cast each turn, you'll be carefully watching for the right opportunity to cast your spells.

Copy your opponents' spells with cards like Expansion // Explosion, Reverberate, and Wild Ricochet. These cards can be particularly helpful early in the game by piggybacking on ramp spells.

Spark Double and Sakashima of a Thousand Faces play a special role in their ability to mimic Kalamax. More Kalamaxes mean more copies and more potential to get through with devastating damage.

Don't be too afraid of opponents laying into your life (unless it's commander damage). You can recover later with cards like Inscription of Abundance and Predator's Rapport.

Opponents who have faced Kalamax understand the risky proposition they face. The category "facebreakers" has cards like Unleash Fury, Invigorating Surge, and Inner Calm, Outer Strength. Opponents may not always want to give up a creature to an attacking Kalamax every turn, but if they don't block, there's a chance that Kalamax's power will suddenly quadruple (or more) and they'll suffer surprise fatal commander damage.

Keep in mind that Mystical Tutor and Worldly Tutor do not benefit from being copied, so cast them after you've already cast an instant that turn.

Berserk stands out as worthy of special instruction - it isn't meant to be used on your own creatures. Look out for one opponent attacking another with a particularly high-power creature. After blockers are declared, make it go Berserk for a very surprising burst of damage. Bonus points if you can kill-assist via commander damage - their commander damage. Other power-boosting cards can be used the same way, but Berserk carries the added benefit of destroying the attacking creature afterward.

This deck may be a gamble - sometimes you unceremoniously lose and other times you explosively win - but sometimes it's better that way. Gotta risk it for the biscuit (credit Bernie).