Valmiki Ramayana Bala Kanda Sarga 21 Shloka 11
Original Shlokaएषोऽस्त्रान् विविधान्वेत्ति त्रैलोक्ये सचराचरे। नैनमन्य: पुमान्वेत्ति न च वेत्स्यन्ति केचन।।1.21.11।।
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एष: this one, विविधान् various kinds of, अस्त्रान् weapons, वेत्ति knows, सचराचरे among all animate and inanimate beings, त्रैलोक्ये in three words, अन्य: पुमान् no other man, एनं न वेत्ति does not know him, केचन none, न वेत्स्यन्ति are not going to know about him in future.
This Viswamitra knows the use of various kinds of weapons which no one knows among the animate and the inanimate in the three worlds. Nor will any one even know in future.