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Three drops like Gaelicat and Tidus, Blitzball Star can rack up damage fast while evading or neutralizing blockers, and Slash of Light will be at its most effective
Snow creatures also give you the opportunity to add +1/+1 counters to your commander, which can get brutal if your opponent isnt drawing into their removal (or running enough of it in the first place)
The fact you have to cast this only after being attacked before blockers and cant be used as a political tool to save another player is why its D-tier
Ancient Lumberknot is another version of this effect that happens to be a treefolk, and Bedrock Tortoise gives you the effect while protecting your creatures during your turn
While Toski is among the smallest creatures with indestructible, the fact that it will survive most board wipes while helping you gain card advantage cannot be overstated